Airport & Underground Coverage: Why Signal Drops and What To Do

31 Oct 2025

Travelling often means jumping from open streets into steel-and-glass terminals and deep underground platforms. It’s no surprise your bars can vanish at the worst moments: boarding passes won’t load, ride-hail pickups fail, and messages loop endlessly. Airport and metro environments are brutal for radio signals, with thick materials, interference, and rapid movement that stress even the best networks. The good news: with a little prep and the right settings, you can keep your phone usable through most weak-signal zones. In this guide, we explain exactly why coverage collapses in airports and tunnels, how modern networks try to fix it (from distributed antenna systems to femtocells and “leaky feeder” cables), and what you can do—step by step—to stay connected. We also cover Wi‑Fi calling as a fallback and what happens if you need to place an emergency call when your device shows no service. If you’re planning trips, we’ll show how the right eSIM choice helps too.

Why airports and subways kill your signal

The physics problem

Materials: Reinforced concrete, metal cladding, and low‑emissivity glass reflect and absorb mobile signals, especially higher‑frequency 4G/5G bands.
Distance and line of sight: You’re often far from macro towers, buried below street level, or behind multiple walls.
Crowds: Thousands of devices in a terminal create contention and interference; uplink (your phone to the network) becomes the bottleneck.

The mobility problem

Handoffs: Moving quickly—airport rail links, shuttles, escalators—forces frequent “handoffs” between cells. If the handoff fails or the next cell is congested, calls drop and data stalls.
Bands and tech mix: Networks may drop you from 5G to 4G to 3G/2G for coverage. Each step down can disrupt active sessions.

The infrastructure gap

Not every venue invests in indoor solutions. Where they do, systems vary:
DAS (Distributed Antenna System): A network of indoor antennas rebroadcasting outdoor cell coverage inside terminals and concourses.
Small cells/femtocells: Mini base stations installed for targeted capacity—lounges, gates, or staff areas.
In tunnels: “Leaky feeder” coaxial cables or dedicated radiating antennas carry mobile signals along the track.
Multi-operator support varies. One operator may have great signal; another may have none.

How networks try to keep you connected

Low-band spectrum: 700–800 MHz bands penetrate buildings better; you’ll often see more bars on these, though speeds may be lower.
Carrier aggregation and DSS: Combine bands or share 4G/5G to keep sessions alive as you move between cells.
VoLTE and VoWiFi: Modern calling stays on 4G/5G or falls back to Wi‑Fi calling, reducing circuit-switched handoff issues.
Priority paths: Airports sometimes prioritise back-of-house and critical services. Public areas may share limited capacity.
Emergency handling: Networks attempt to place emergency calls on any available cell, sometimes even on a rival network, depending on local regulations.

Before you go: a 10‑minute prep checklist

Install a local or regional eSIM - A multi-network or strong local profile can massively improve indoor performance. - Regional options like Esim Western Europe or Esim North America let your phone choose among partner networks. - Check country specifics on Destinations or install a country plan such as Esim United States, Esim France, Esim Italy, or Esim Spain.
Enable Wi‑Fi calling - iOS: Settings > Mobile Data > Wi‑Fi Calling. - Android (varies): Settings > Network & Internet > Mobile network > Wi‑Fi calling. - Confirm your phone shows “Wi‑Fi” or an icon in the dialler when active.
Download essentials for offline access - Boarding passes, rail tickets, hotel directions, offline maps, and translation packs. - Authentication apps: sync or note backup codes to avoid SMS dependency.
Adjust network settings - Prefer 4G/5G Auto; avoid “5G Only”. - Turn on Data Saver/Low Data Mode to handle captive Wi‑Fi and weak uplinks.
Power plan - Weak signal drains batteries fast. Start with 70%+ and carry a power bank.

Pro tip: Add airline and airport apps to “unrestricted battery” so they can load passes on flaky connections.

At the airport: practical tactics that work

Use venue connectivity wisely

Join official airport Wi‑Fi and complete the captive portal; Wi‑Fi calling may not activate until the portal is cleared.
If Wi‑Fi calling still won’t engage:
Toggle Airplane Mode on, then enable Wi‑Fi only to force calling over Wi‑Fi.
Disable VPN temporarily; some VPNs block Wi‑Fi calling’s IMS traffic.
Forget and rejoin Wi‑Fi if the portal pops up again.

Choose your spot

Near windows or open atriums generally improves signal.
Avoid dense metal structures (security lanes) and sublevels when placing important calls.
Lounges may have small cells; a quick signal check can be worthwhile.

Manage handoffs

If a call keeps dropping as you move, step aside and finish the call stationary.
For video calls, switch to audio or pause video while walking between concourses.

If data stalls but bars look fine

Try switching to 4G/LTE from 5G; some indoor DAS nodes still deliver steadier 4G.
Toggle Mobile Data off/on, or briefly toggle Airplane Mode to trigger reselection.
Manually select a different network if your eSIM allows it.

Pro tip: Some gates have better indoor coverage because they sit under newer DAS clusters. If you find one that loads fast, stay put while you upload photos or sync documents.

Underground and on the metro: what’s different

Not all lines have mobile coverage. Some systems cover platforms only, others include tunnels, and some rely purely on station Wi‑Fi.
Coverage can switch every few hundred metres as the train passes tunnel antennas, causing brief dropouts.
Speed matters: fast lines can outrun small-cell footprints, making uplink patchy.

Staying connected below ground

Make Wi‑Fi your default:
Set your phone to auto-join official metro Wi‑Fi; finish any captive portal step at the first station.
Keep Wi‑Fi calling enabled. You can often place calls and send messages between stops.
Prepare for tunnel blackouts:
Queue messages and downloads.
Use offline navigation between stations and refresh when the train stops.
For critical tasks:
Wait for a station with platform coverage.
If you must call, stand near the platform centre where antennas are typically positioned.

Pro tip: If the metro has partial coverage, switch chat apps to “low bandwidth” or audio-only modes to ride out tunnel gaps.

What if you need to call emergency services?

Your phone will attempt to place emergency calls (e.g., 112, 911, 999) on any available network, even if your own provider has no service. This behaviour depends on local regulations and device support but is widely implemented.
If you see “No Service”:
Try the emergency number anyway; the phone will scan for any cell that can carry the call.
Move towards open areas, station entrances, or near windows to improve odds.
Wi‑Fi calling and emergencies:
In many countries, emergency calls are supported over Wi‑Fi calling, but not everywhere. If Wi‑Fi is the only option, complete the captive portal and try—your phone will choose the best available path.
If Wi‑Fi calling is unavailable for emergency calls, the device will attempt cellular instead.
Location sharing:
Modern systems can transmit your location (Advanced Mobile Location/AML) when you call emergency numbers. This may not work over all Wi‑Fi networks.

Note: Rules and capabilities vary by country and operator. If in doubt, move to an area with clear cellular coverage as soon as it’s safe.

Troubleshooting quick wins

Try these in order when signal or data misbehaves:

Toggle Airplane Mode on for 10 seconds, then off.
Turn Wi‑Fi off and on; complete any captive portals.
Switch network mode to 4G/LTE and back to 5G Auto later.
Manually select a different partner network (if your eSIM allows).
Reset network settings only if the above fails (you’ll need to rejoin Wi‑Fi networks).

Pro tip: Save your eSIM QR and plan details offline before you travel in case you need to reinstall after a network reset.

Picking the right eSIM for hard-to-reach places

Prefer plans with multi-network access in your destination so your phone can latch onto the operator with the best indoor/DAS presence.
If you’re visiting multiple countries or transiting through major hubs, regional eSIMs simplify coverage:
Esim Western Europe for intra‑EU travel where metro coverage varies city by city.
Esim North America for the US and Canada, where low-band 5G/4G differs by carrier and airport DAS deployments are uneven.
Country-specific options can outperform roaming in airports with single-operator DAS:
Esim United States
Esim France
Esim Italy
Esim Spain
Check operator notes and airport/metro coverage on Destinations.

For teams on the move, pooled data and policy controls help ensure staff stay reachable in terminals and tunnels. See For Business for options. Venue and travel partners exploring indoor solutions can visit our Partner Hub.

Tech corner: femtocells, DAS, and “leaky feeders” explained

Femtocells and small cells: Low‑power base stations that improve coverage in a small area like a lounge or gate cluster. They attach to backhaul (often fibre) and broadcast licensed spectrum.
DAS: A centralised system that pulls in operator signals and redistributes them via fibre/coax to many indoor antennas. Great for large airports where uniform coverage is needed.
Leaky feeder cables: Special coax that acts like a long antenna, “leaking” RF along tunnels so trains and platforms receive consistent signal. Common in metros and long airport service tunnels.
Handoffs: Your device measures signal quality and the network commands a move to a better cell. In dense or poorly tuned systems, handoffs can fail, causing drops. Staying still during calls helps.

Fast setup steps (iOS and Android)

Force Wi‑Fi calling
iOS: Control Centre > enable Airplane Mode > turn Wi‑Fi back on > ensure “Wi‑Fi” shows in the Phone app status line.
Android: Quick Settings > Airplane Mode > enable Wi‑Fi; confirm Wi‑Fi calling icon in the dialler or status bar.
Lock to LTE temporarily
iOS: Settings > Mobile Data > Voice & Data > 4G.
Android: Settings > Network & Internet > Mobile network > Preferred network type > LTE/4G.
Switch networks
iOS: Settings > Mobile Data > Network Selection > turn off Automatic and pick another partner.
Android: Settings > Mobile network > Network operators > Search networks.

Pro tip: After leaving the airport or surfacing from the metro, return to Automatic network selection and 5G Auto.

FAQs

Why do I have full bars but no data in an airport?
Indoor systems can show strong signal but be congested on the backhaul or uplink. Try switching to 4G/LTE, move to a quieter spot, or use airport Wi‑Fi with Wi‑Fi calling.
Does 5G work underground?
Often only low‑band 5G or 4G is deployed in tunnels. High‑band 5G (especially mmWave) struggles with penetration and is rare below ground.
Will Wi‑Fi calling charge me roaming fees?
Wi‑Fi calling uses the internet, not cellular roaming, but call billing depends on your home operator. For data, airport Wi‑Fi is typically free or time‑limited. Using a local eSIM avoids surprises.
Can I rely on emergency calls without mobile coverage?
Your phone will try any available cellular network for an emergency call. It may also attempt the call over Wi‑Fi if supported. This is common but not guaranteed everywhere.
Why does my battery drain faster in terminals and tunnels?
Phones boost transmit power and scan more aggressively when signal is weak. Use Low Power Mode, keep a power bank handy, and prefer Wi‑Fi when available.
Should I turn off 5G to save battery indoors?
Sometimes. If 5G is weak or inconsistent, locking to 4G can stabilise connectivity and reduce scanning.

The bottom line

Airports and underground systems are challenging radio environments. Expect reflections, rapid handoffs, and capacity crunches—then prepare accordingly: enable Wi‑Fi calling, carry a multi‑network eSIM, download essentials for offline use, and know a few quick toggles to recover service when it falters. With the right setup, you’ll get your boarding pass, message your pickup, and place calls even when your bars dip.

Next step: Choose a regional plan that keeps you covered across borders and terminals. Start with Esim Western Europe.

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Andes Highlights (3 Weeks): Peru–Bolivia–Chile–Argentina Connectivity

Planning a south america itinerary 3 weeks through the high Andes? This route stitches together Peru’s Sacred Valley, Bolivia’s La Paz and Salar de Uyuni, Chile’s Atacama Desert, and northern Argentina’s quebradas or Mendoza wine country—often by long-distance bus and a couple of short flights. Connectivity is different at altitude: coverage is strong in cities but drops in high passes and salt flats; bus Wi‑Fi is patchy; border towns can be blackspots. The smart move is an eSIM with multi‑country coverage, backed by offline maps, offline translations, and a simple routine for crossing borders by bus without losing service. Below you’ll find a practical, connectivity-first itinerary; checklists to prep your phone, apps and documents; and on-the-ground tips for staying online where it matters: booking transport, hailing taxis, backing up photos, and navigating when the signal disappears.If you’re transiting via Europe or North America, you can also add a layover eSIM to stay connected door-to-door. Start with our country list on Destinations, then follow the steps, and you won’t waste time chasing SIM shops at 3,500 metres.The 3‑week Andes route at a glanceWeek 1: Peru (Cusco, Sacred Valley, Machu Picchu) - Fly into Cusco (or Lima then connect). - Base in Cusco; day trips to Pisac/Chinchero/Maras–Moray. - Train to Aguas Calientes; Machu Picchu visit; return to Cusco or continue to Puno/Lake Titicaca.Week 2: Bolivia and Chile (La Paz, Uyuni, San Pedro de Atacama) - Bus/collectivo via Copacabana to La Paz. - Fly or overnight bus to Uyuni. - 3‑day Uyuni–altiplano tour ending in San Pedro de Atacama (Chile).Week 3: Chile and Argentina (Atacama to Salta or Mendoza/Buenos Aires) - Choose: - North: San Pedro to Salta/Jujuy by bus; fly to Buenos Aires. - Or South: San Pedro–Calama flight to Santiago; bus or flight to Mendoza; onward to Buenos Aires.Connectivity notes (quick): - Cities: generally strong 4G/4G+; 5G in major hubs (Santiago, Buenos Aires). - Altitude/rural: expect long no‑signal stretches (Uyuni, altiplano passes, Paso Jama). - Bus Wi‑Fi: often advertised, rarely reliable. Plan to be offline onboard. - Border regions: networks switch; a multi‑country eSIM avoids sudden loss.eSIM vs local SIMs for a 4‑country tripFor a route with multiple borders and remote legs, eSIM wins on time and reliability.What a multi‑country eSIM gets you: - One plan across Peru, Bolivia, Chile, Argentina (check coverage per country on Destinations). - No passport/SIM registration queues at kiosks. - Keep your home number active on the physical SIM for calls/SMS codes. - Instant top‑ups if you burn data on photos or navigation.When a local SIM still helps: - Long stay in one country with heavy data use (e.g., a month in Buenos Aires). - Dead zones where a different local network performs better (rarely worth the hassle on a 3‑week pace).Practical approach: - Use an eSIM as your primary data line across all four countries. - If you find a specific local network far better in one region, add a cheap local SIM and keep the eSIM as backup.Device readiness checklist (before you fly)1) Check eSIM compatibility and SIM‑lock status on your phone.2) Buy and install your eSIM while on home Wi‑Fi. Keep a PDF/printed copy of the QR code.3) Label lines clearly (e.g., “eSIM Andes Data”, “Home SIM”).4) Turn on data roaming for the eSIM; leave roaming off for your home SIM to avoid charges.5) Set up dual‑SIM rules: data on eSIM; calls/SMS default to home SIM if needed.6) Download offline: Google Maps/Organic Maps for all target regions; language packs (Spanish at minimum); bus/air tickets; hotel confirmations.7) Cloud backups: set to upload on Wi‑Fi only; pre‑create shared albums for travel companions.8) Test tethering/hotspot with your laptop/tablet.If you’re transiting popular hubs, consider a short layover eSIM: - USA connections: add an Esim United States or a broader Esim North America.- Europe connections: Madrid/Barcelona? Use an Esim Spain. Paris or Rome? See Esim France and Esim Italy. Multi‑country layovers? Try Esim Western Europe.City‑by‑city connectivity notesCusco & the Sacred Valley (Peru)Coverage: Good in Cusco city; variable in high villages (Maras/Moray) and along Inca Trail approaches.Tips: Download Sacred Valley maps offline; pin viewpoints and ruins. most taxis use WhatsApp—save your accommodation’s number.Machu Picchu/Aguas Calientes: Patchy to none at the citadel. Upload your photos later; don’t rely on live ticket retrieval.Lake Titicaca: Puno and CopacabanaPuno: Reasonable 4G; bus terminals crowded—screenshot QR tickets.Crossing to Copacabana: Expect a signal drop around the border; have directions saved offline.La Paz (Bolivia)Good urban 4G; the cable car network has decent signal but tunnels do not.Yungas/“Death Road” tours: Mountain valleys cause dead zones—share your emergency contacts with the operator, carry a charged power bank, and don’t plan remote calls.Uyuni and the Altiplano (Bolivia to Chile)Uyuni town: OK 4G; ATMs finicky—use Wi‑Fi for banking apps.Salt flats/lagunas: Assume offline for most of the 3‑day tour. Guides often carry satellite phones; agree a pickup time/place in San Pedro and preload your map route.San Pedro de Atacama (Chile)Town: Solid 4G; accommodations often have Wi‑Fi but speeds vary.Geysers, Valle de la Luna: Offline navigation essential; sunrise trips start before mobile networks wake up in some areas.Salta/Jujuy or Mendoza/Buenos Aires (Argentina)Salta/Jujuy: Good city coverage; quebradas have long no‑signal sections.Mendoza: City 4G/5G; vineyards outside town can be patchy.Buenos Aires: Strong 4G/5G; ideal for cloud backups and large downloads before you fly home.Border crossings by bus: step‑by‑stepThe big ones on this route: Peru–Bolivia (Puno/Copacabana), Bolivia–Chile (Uyuni–San Pedro via Hito Cajón), Chile–Argentina (Paso Jama to Salta or Los Libertadores to Mendoza).How to keep service and sanity:1) The day before:- Top up your eSIM data.- Confirm your plan includes both countries you’re entering/leaving.- Download offline maps for both sides of the border and your town of arrival.- Save bus company WhatsApp and terminal address offline.2) On departure morning:- Keep a paper copy or offline PDF of tickets, insurance, and accommodation proof.- Charge phone and power bank; pack a short cable in your daypack.3) On the bus:- Don’t count on bus Wi‑Fi. Keep your eSIM as primary, but expect drops near mountain passes.- If your phone supports it, enable “Wi‑Fi calling” for later when you reach accommodation Wi‑Fi.4) At the border posts:- Data may be unavailable. Keep QR codes and booking numbers offline.- After exiting one country and entering the next, toggle Airplane Mode off/on to re‑register on the new network.- If the eSIM doesn’t attach, manually select a network in Mobile Settings.5) Arrival:- Send your accommodation a quick WhatsApp when you’re back online.- Recheck your eSIM’s data roaming is on; confirm you’re on an in‑country network, not a weak roaming partner.Pro tips: - Dual profiles: If your eSIM allows, keep a secondary profile for a different network in the same country—helpful in border towns.- Cash buffer: Some border terminals don’t accept cards; download a currency converter for offline use.Offline survival kit (5‑minute setup)Maps: Download regions for Cusco, Sacred Valley, Puno, La Paz, Uyuni, San Pedro, Salta/Jujuy or Mendoza, and Buenos Aires.Translations: Download Spanish for offline use; add phrasebook favourites (bus tickets, directions, dietary needs).Documents: Save PDFs of passports, tickets, hotel addresses; star them for quick access.Rides: Screenshots of pickup points; pin bus terminals and hotel doors.Entertainment: Podcasts and playlists for long bus legs, set to download on Wi‑Fi only.Altitude and your tech: what changesCoverage gaps lengthen: Fewer towers at high altitude; valleys can block signal. Assume offline on remote excursions.Batteries drain faster in cold: Keep your phone warm and carry a power bank (10,000–20,000 mAh).Hotel Wi‑Fi may be congested: Schedule big uploads (photo backups, app updates) for big-city stays like Santiago or Buenos Aires.GPS still works offline: Your blue dot shows on offline maps without data—preload everything.Data budgeting for 3 weeksTypical traveller usage across this route: - Messaging/Maps/Bookings: 0.2–0.5 GB/day- Social and photo sharing: 0.3–0.7 GB/day- Occasional video calls/streaming: 0.5–1.0 GB/dayFor a mixed-use trip, plan 15–25 GB for 3 weeks. Heavy creators should double it and upload over hotel Wi‑Fi when possible. If you work remotely, consider a higher‑capacity plan and a backup eSIM; see our guidance on For Business.Practical route with transport and connectivity cuesDays 1–4 Cusco base: Strong city signal; day trips may be spotty—go offline-ready.Days 5–6 Machu Picchu: Expect no service at the ruins; sync tickets ahead.Days 7–8 Puno to La Paz via Copacabana: Border signal drop; re‑register networks after crossing.Days 9–11 Uyuni tour to San Pedro: Treat as offline; charge nightly; carry spare cables.Days 12–14 San Pedro: Stable in town; tours offline; top up data before Paso Jama.Days 15–17 Salta/Jujuy or Mendoza: Good urban 4G; rural patches are offline.Days 18–21 Buenos Aires: Strongest connectivity of the trip; clear your uploads and map downloads for the flight home.Partnering and stopover extrasHospitality and tour operators in the Andes: help your guests stay connected—explore co‑branded solutions via our Partner Hub.Transatlantic flyers: test your eSIM setup on a layover with an Esim United States or Esim Western Europe before hitting high-altitude blackspots.FAQs1) Do I need a local SIM in each country?No. A multi‑country eSIM covering Peru, Bolivia, Chile and Argentina is simpler and works well for a 3‑week pace. Consider a local SIM only if you’ll spend longer in one country and want the absolute best regional coverage.2) Will my WhatsApp number change with an eSIM?No. WhatsApp is tied to your registered number, not your data line. Keep your home SIM active for voice/SMS (roaming off if you wish), and use the eSIM for data—WhatsApp continues as normal.3) Can I hotspot to my laptop or camera?Yes. Enable tethering on your eSIM. Mind your data: cloud backups and OS updates can burn gigabytes—set them to Wi‑Fi only or schedule in big cities.4) What if there’s no signal on the Uyuni/Atacama legs?That’s expected. GPS still works offline. Pre-download maps and translations, carry a power bank, and sync plans with your tour operator before departure.5) Will I get roaming charges at borders?If you’re using a multi‑country eSIM with coverage in both countries, you won’t incur extra roaming fees from your home carrier. Keep roaming off on your home SIM to avoid accidental use.6) I’m connecting via Europe or the US—worth getting a layover eSIM?Yes. It’s an easy way to test your setup and stay reachable. Try Esim North America or country options like Esim Spain, Esim France, or Esim Italy for common hubs.Next step: Browse South America coverage options and build your plan on Destinations.

31 Oct 2025

eSIM Compatible Phones (Updated 2025): iPhone, Samsung, Pixel & More

Travellers are ditching plastic SIMs for eSIMs because they’re fast to set up, kinder to your phone’s SIM tray, and usually cheaper than roaming. But eSIM support varies by model and region, and not every “dual-SIM” phone actually supports a digital SIM. This 2025 guide gives you the definitive compatibility picture: quick checks you can run in under two minutes, a brand-by-brand device matrix, and practical install tips that avoid airport Wi‑Fi panic. If you’re planning a trip to the US, Europe or beyond, we’ll also point you to dependable regional plans like Esim United States, Esim Western Europe and Esim North America.Key point: model names alone aren’t enough. Variants from different countries or carriers can enable or disable eSIM. Use the quick checks below to confirm your exact device, then pick a plan from our global Destinations page.The fastest way to confirm eSIM support (2‑minute check)Step 1: Find your EIDiPhone: Settings > General > About. Look for “EID”.Android (Pixel/Samsung/others): Settings > About phone (or Status). Look for “EID”.Or dial *#06# on most phones. If you see an EID, your hardware supports eSIM.Step 2: Look for an “Add eSIM” optioniPhone: Settings > Mobile Data > Add eSIM.Samsung: Settings > Connections > SIM manager > Add eSIM.Pixel/Android: Settings > Network & Internet > SIMs > + Add eSIM.Step 3: Update and unlockInstall the latest iOS/Android update.Ensure the phone is network unlocked for travel eSIMs.Step 4: Dual SIM expectationsMost recent iPhones, Pixels and flagships support two lines active (one or two eSIMs depending on model). Mid‑range Androids may allow only one eSIM active alongside a physical SIM.Pro tip: No EID showing? Your model or region variant likely doesn’t support eSIM, or the feature is disabled by firmware/carrier.eSIM‑compatible phones in 2025: the definitive listModel availability and eSIM features can vary by region and carrier firmware. Use this as a guide, then run the quick checks above on your exact handset.Apple iPhone (global leaders for eSIM)iPhone 16 / 16 Plus / 16 Pro / 16 Pro Max – eSIM supported; US models are eSIM‑only (no SIM tray).iPhone 15 family – eSIM supported; US models are eSIM‑only.iPhone 14 family – eSIM supported; US models are eSIM‑only.iPhone 13, 12, 11 families – eSIM supported.iPhone XS, XS Max, XR – first iPhones with eSIM.iPhone SE (2nd gen 2020, 3rd gen 2022) – eSIM supported.Notes for travellers: - iPhone 13 and newer can run two eSIMs simultaneously (or one eSIM + one physical SIM on non‑US models). - iOS allows storing multiple eSIM profiles and switching as you travel.Samsung Galaxy (flagships and many A‑series)Galaxy S24 / S23 / S22 / S21 / S20 series – eSIM supported on most global variants.S20 FE: eSIM availability depends on edition/region; later “2022” models added eSIM in many markets.Galaxy Z Fold and Z Flip (all generations since eSIM was introduced) – eSIM supported.Galaxy Note20 / Note20 Ultra – eSIM supported on most variants.Galaxy A‑series (region‑dependent): A55, A54, A35, A34, A25 5G, A15 5G and newer mid‑range models often include eSIM in Europe/Asia; some US carrier‑branded units disable it.Notes for travellers: - eSIM on Samsung can be region/carrier dependent. Check Settings > Connections > SIM manager. - Many newer models support multiple stored eSIMs; simultaneous active lines vary by device/firmware.Google Pixel (Android’s eSIM reference)Pixel 9 / 9 Pro / 9 Pro Fold – eSIM supported.Pixel 8 / 8 Pro – eSIM supported; dual eSIM possible on recent Android builds.Pixel 7 / 7 Pro / 7a – eSIM supported.Pixel 6 / 6 Pro / 6a – eSIM supported.Pixel 5 / 4 / 4a – eSIM supported.Pixel 3 / 3a – eSIM supported in many regions; some carrier variants limit it.Pixel Fold – eSIM supported.Notes for travellers: - Pixel 2 had a limited eSIM implementation (mostly Google Fi); treat it as non‑universal.- Keep Android 13+ for the smoothest eSIM experience.Other Android brands (selected models with widespread eSIM support)Because eSIM on these brands varies more by market and firmware, treat this as “supported in many regions” and confirm on your device with the EID check.OnePlus: 11, 12, 13 – eSIM on many EU/IN/global variants; earlier models largely lacked eSIM.Sony Xperia: 1 V/VI, 5 V, 10 V/VI – eSIM widely supported.Motorola: Razr (2019 onwards), Razr 40/50 series; Edge 30/40 families and newer – many variants support eSIM.Xiaomi: 13 / 13 Pro / 13T Pro, 14 / 14 Pro / 14 Ultra – growing eSIM support by region; confirm locally.OPPO: Find X5/X6/X7 series; Reno 8/10 series – selected regional variants support eSIM.Huawei: Selected P and Mate series (e.g., P40/P50/P60, Mate 40/50) support eSIM in some markets.Nothing: Phone (1) and Phone (2) support eSIM.Fairphone: Fairphone 4 and 5 support eSIM.Nokia/HMD: Nokia X30 5G, XR21 and some enterprise models support eSIM.Pro tips: - Mid‑range and carrier‑branded Androids are the most inconsistent. Always check for EID and an “Add eSIM” option. - If your dual‑SIM tray has two physical SIM slots, eSIM may still be supported—but it’s not guaranteed.iPhone vs Samsung vs Pixel on the roadiPhoneBest overall consistency. US iPhone 14/15/16 are eSIM‑only, which is ideal for travel plans.iOS makes it simple to label lines (e.g., “Japan Data”) and pick a default for data/voice.Can store multiple profiles; two lines active on iPhone 13 and newer.SamsungPowerful SIM manager with clear toggles for data/voice/roaming.Watch for model/region variance on A‑series and FE models.If “Add eSIM” is missing, update software; some regions enable it via firmware.PixelClean implementation with helpful prompts; strong dual‑SIM standby on recent models.Updating to the latest Android build often unlocks dual eSIM improvements.Great for quick QR installs before you fly.How to install a Simology eSIM (step‑by‑step)Do this on Wi‑Fi before you travel.1) Buy a plan- Choose your country or region on Destinations. For multi‑country trips, consider Esim Western Europe or Esim North America.2) Open your QR or activation details- Keep the email/app screen open on another device, or print the QR.3) Add the eSIM- iPhone: Settings > Mobile Data > Add eSIM > Use QR Code.- Samsung: Settings > Connections > SIM manager > Add eSIM > Scan QR.- Pixel: Settings > Network & Internet > SIMs > + Add eSIM.4) Label and set defaults- Name it (e.g., “Trip EU”) and set it as the Mobile Data line. Keep your primary line for calls/texts if needed.5) Enable Data Roaming on the travel eSIM- Required for regional packs like Esim France, Esim Italy or Esim Spain.6) Test before departure- Toggle the eSIM off/on and check APN auto‑config. You’re ready.Pro tips: - Arriving late? Install the eSIM at home so it activates instantly on landing.- Use regional bundles to avoid switching plans mid‑trip (e.g., Esim United States for the US or Esim Western Europe for multi‑country EU travel).- Business travellers: centralise purchasing and compliance with For Business.Troubleshooting and gotchasNo “Add eSIM” optionUpdate software; reboot; check if the phone is carrier‑branded (some carriers hide the menu on mid‑range models).No EID foundYour device likely lacks eSIM hardware or the variant disables it.QR won’t scanEnter activation details manually. Ensure you’re on Wi‑Fi and any VPN is off.“Maximum eSIMs reached”Delete old, unused eSIM profiles to free a slot.Data not working on arrivalConfirm the travel eSIM is set as the Mobile Data line and Data Roaming is on. Reboot once after network attach.Locked phoneTravel eSIMs require an unlocked device. Contact your carrier to request unlock before you fly.Partners and resellers: streamline onboarding and co‑branded offers via the Partner Hub.FAQHow do I know if my phone is eSIM capable?Check for an EID in Settings (or dial *#06#) and an “Add eSIM” option in your SIM settings. If both exist, your phone supports eSIM. If either is missing, it likely doesn’t.Do I need an unlocked phone to use a travel eSIM?Yes. Most travel eSIMs, including Simology plans, require an unlocked device. A carrier‑locked phone generally only accepts that carrier’s eSIMs.Can I run two lines at the same time?Most modern iPhones (13 and newer) and recent Pixels/Samsungs support two active lines (e.g., personal number plus travel data). Some mid‑range Androids limit you to one active eSIM at a time.How many eSIMs can I store?It varies by model. Recent iPhones and Pixels can store multiple eSIM profiles (often 5–10 or more) but typically allow only two lines active simultaneously. You can switch profiles in Settings.Can I move an eSIM to a new phone?Some providers support eSIM transfer in‑app or via QR reissue, but many treat eSIMs as one‑device only. Plan to install a fresh eSIM on your new phone.Will eSIM drain my battery faster?Not noticeably. Running two lines can use slightly more power, but modern radios manage this efficiently. Most users won’t see a meaningful difference.Next step: Confirm your phone with the quick checks above, then pick your destination plan on Destinations.

30 Oct 2025

Multi‑Network Smart Switching for Partners: SLA Uplift & Fewer Support Tickets

Modern travellers expect connectivity that “just works”, anywhere, anytime. For partners and wholesalers, that means delivering resilient mobile data that rides over multiple networks and quietly switches when conditions degrade. Multi‑network smart switching turns a single‑carrier promise into a carrier‑diverse service level, lifting uptime, lowering latency and slashing support noise when customers cross borders or move between urban and rural cells. This article explains how smart switching works, what uplift to expect in real numbers, and how to frame it in your sales deck. We’ll cover SLA design, implementation checklists, and practical measurement so you can prove more minutes of service delivered, fewer “no service” moments and faster apps. If you sell travel eSIM across regions such as Esim Western Europe and Esim North America, smart switching is the most efficient path to better SLAs and fewer escalations—without asking end users to fiddle with settings or swap profiles.What is multi‑network smart switching?Multi‑network smart switching is a policy‑driven capability embedded in the SIM/eSIM stack that selects the best available network at any moment, based on real‑time quality signals such as:Radio availability and signal qualityAttach success/failure and PDP/PDN session stabilityLatency to key targets (e.g., DNS, CDN edges)Packet loss and jitterCommercial rules (whitelists/blacklists, cost ceilings, fair use)Instead of pinning a device to a single carrier, your eSIM has access to multiple MNOs/MVNOs in each country. A lightweight policy engine monitors quality and triggers network reselection or profile steering if the current path degrades.For travellers, the experience is invisible: the device stays online as they move from, say, Paris to Barcelona (see Esim France and Esim Spain), or from New York to California (Esim United States). For partners, it’s the simplest way to add resilience and meet enterprise‑grade expectations across our Destinations.Why smart switching matters for SLAsQuantifying uptime upliftIf you rely on a single network with 99.0% monthly availability, that’s about 7 hours and 18 minutes of downtime per month. With access to two independent networks of similar quality, the combined availability approaches:Combined availability ≈ 1 − (1 − A1) × (1 − A2)Example with A1 = 0.990 and A2 = 0.990 → 1 − 0.01 × 0.01 = 99.99%Real‑world failures are not perfectly independent (storms, fibre cuts, or national outages can hit multiple networks), so a conservative planning assumption is:Single‑network monthly downtime: 200–450 minutes (varies by market granularity)Dual/triple‑network smart switching downtime: 5–30 minutesPractical uplift: 10× to 40× less downtime, translating into 99.95%–99.99% delivered availabilityEven a modest two‑network design with correlated risks typically lifts availability from 99.0–99.5% to 99.95%+. Across an active travel cohort, that’s hundreds of “saved” online minutes per 1,000 user‑days.Latency and app performanceChoosing the lowest‑latency path matters for cloud apps, maps and messaging. Smart switching prefers networks with:Local or regional breakout rather than home‑routed trafficHealthier peering to major CDNs and collaboration suitesLower radio congestion in the momentObserved results partners can expect:EU intra‑region p95 latency improvements of 20–40% when switching to a better‑peered MNO (e.g., from 120–160 ms to 70–110 ms)Within the US, p95 latency reductions of 15–30% by avoiding congested areas or leveraging a stronger regional carrier10–25% reduction in time‑to‑first‑byte for common mobile web flowsFor many travel use cases, perceived speed is as valuable as raw throughput. Lower p95 latency (not just averages) is what keeps video calls and maps usable.Support ticket reductionMost travel connectivity tickets cluster into a few buckets:No service / can’t attach“Data is slow”Intermittent dropsAPN/profile confusionSmart switching prevents the first three by auto‑moving away from bad cells, degraded cores or poorly performing peering. Typical reductions once deployed:30–50% fewer “no service” tickets20–35% fewer “slow data” tickets40–60% drop in intermittent dropouts, especially at cell edges and transit hubsFewer incidents means lower support cost per account and happier travellers—reflected in higher CSAT/NPS.How smart switching works in practiceMulti‑MNO access per country: eSIM profiles grant access to multiple carriers in markets covered by products such as Esim Western Europe, Esim North America, and country packs like Esim Italy.Policy‑based steering: The eSIM stack and partner platform set preferred/forbidden networks and thresholds for switching (e.g., persistent packet loss, repeated attach failures, or sustained high latency).Fast, graceful failover: Devices usually reselect within seconds when a better cell is available; full context rebuild may take longer when moving between cores. End users typically experience a brief blip rather than an outage.Compliance‑aware: Partners can restrict selection to specific networks for regulatory or contractual reasons, while still maintaining diversity where permitted.Note: switching behaviour can vary by device OS and modem firmware. Always include device diversity in your test plan.Designing a multi network switching SLAA robust multi network switching SLA should define:Coverage scope: Countries/regions and included technologies (4G/5G NSA/SA; 2G fallback where applicable).Availability target: e.g., 99.95% monthly at the service edge (successful data session and reachability to defined targets).Latency: p95 thresholds to strategic targets (e.g., 100 ms within region), plus packet loss/jitter bounds.Attach success: e.g., >99.8% attach success within three attempts.Time‑to‑recover: e.g., recovery within 60 seconds from RAN loss where another network is available.Maintenance windows: whether counted or excluded.Measurement method: synthetic probes, device telemetry, or both; time‑zone and aggregation rules.Credits/remedies: aligned to impact, not just percentage figures.Practical baseline examples to include in proposals:Expected availability: 99.95–99.99% across Tier‑1 markets; 99.9–99.95% in challenging geographies.p95 latency targets: 70–110 ms in Western Europe; 60–120 ms across the United States; 90–140 ms cross‑border in North America.Typical downtime minutes avoided vs. single‑network: 150–400 minutes per month saved at scale.Caveat: When multiple carriers share common infrastructure (e.g., the same backhaul or data centre), failures may correlate. Build safety margins into your SLA targets and document assumptions.Implementation checklist for partners1) Select the right products and footprint - Map travel routes against our Destinations. - Choose regional packs where roaming density is high, like Esim Western Europe. - For US‑heavy travel, include Esim United States and broader Esim North America.2) Define policy and constraints - Whitelist preferred networks per country; blacklist known weak cells where needed. - Set switching thresholds (attach retries, packet loss %, p95 latency ceilings). - Add compliance rules (e.g., force domestic breakout for specific roles).3) Prepare devices - Validate APN and OS versions; ensure eSIM installation flow is clear. - Test both iOS and Android, including dual‑SIM scenarios.4) Run a structured field test - Build a route‑based test matrix (airports, transit, hotels, rural). - Collect p95 latency, packet loss, attach success, and time‑to‑failover.5) Operationalise monitoring - Set up synthetic probes in key cities (e.g., Paris, Milan, Madrid, New York). - Alert on threshold breaches and trigger automated steering adjustments.6) Update support playbooks - Replace “toggle airplane mode” scripts with “smart switching check” steps. - Categorise tickets to isolate improvements in the first 60 days.7) Close the SLA loop - Publish monthly reports with uptime minutes delivered, p95 latency, and ticket volume changes. - Share before/after comparisons with enterprise customers.Pro tip: Keep policy simple to start. Two‑tier thresholds (degradation and failover) often outperform complex rule stacks and are easier to explain in an SLA.Measuring outcomes: before/after that executives understandTrack and report the metrics that translate to traveller experience and support load:Downtime minutes per 1,000 user‑daysp95 latency by country and by hour of dayAttach success rate and PDP/PDN drop rateTime‑to‑failover when quality degradesTicket volumes by category and severityCSAT/NPS for connectivity over timeBenchmarks seen after rollout:Downtime per 10,000 user‑days: from 500+ minutes down to 50–150 minutesp95 latency: 20–40% reduction in Western Europe and 15–30% across the USAttach failure rate: 25–50% reductionSupport tickets: 35–55% reduction overall; first‑response times down by 20–30%These results form the backbone of your SLA narrative and your sales proof points.How to position smart switching in your sales deckStructure your pitch around outcomes, not internals:Headline: “Always‑on travel connectivity with carrier diversity. 99.95%+ delivered availability. Auto‑failover in seconds.”Visual: Route map with overlapping carrier coverage; a call‑out of “no single‑carrier dependency”.Benefits slide:10–40× fewer downtime minutes vs. single‑network roaming20–40% lower p95 latency in key markets35–55% fewer support ticketsZero user action required; seamless device experienceProof points:Before/after metrics from a pilot on Esim Western EuropeUS results from Esim United StatesSLA summary: Clear targets for availability, latency, time‑to‑recover, and measurement approachBuyer‑friendly close: “Start with a 60‑day pilot, monitored and co‑managed.”Pro tip: Put p95 latency on the same slide as collaboration app performance (e.g., “Teams/Meet calls stay stable at p95 < 110 ms”). Stakeholders can connect the dots instantly.Where smart switching helps mostFrequent‑traveller teams moving between EU countries (Paris–Milan–Barcelona) with Esim France, Esim Italy and Esim SpainUS‑centric road warriors relying on robust coverage across states with Esim North AmericaPop‑up retail and events that cannot tolerate single‑cell congestionField service in rural areas where one network often outperforms othersCritical apps that are latency‑sensitive (payments, UCaaS, live translation)Pro tips for smooth operationsKeep the APN consistent across products to simplify device setup and MDM policies.Monitor p95, not just averages. It’s where user pain lives.Maintain a minimal “known good networks” list per country and review quarterly.Educate users that brief blips can occur during switching; the system is protecting them from longer outages.Use synthetic probes near airports and train stations—congestion there is a leading indicator for broader issues.FAQQ: How is smart switching different from traditional roaming steering?A: Traditional steering prioritises a preferred roaming partner for commercial reasons. Smart switching prioritises real‑time quality and resilience, moving between multiple networks to protect the user experience and SLA.Q: Will frequent switching drain battery?A: Properly tuned policies avoid flapping. Devices remain attached until quality falls below thresholds, then reselect. In practice, battery impact is negligible compared to the gains from avoiding repeated manual toggling or stalled apps.Q: Does the IP address change when the device switches?A: It can. Moving to a different core or breakout may change IP. For most travel use cases that’s fine. If you require session persistence, design app logic to handle IP changes or pin traffic via a corporate VPN.Q: Can we restrict networks for compliance or cost?A: Yes. You can whitelist/blacklist networks per country while preserving diversity within the allowed set. Document these constraints in the SLA so expectations remain clear.Q: What happens in areas with limited technology (e.g., only 4G available)?A: Smart switching still helps by selecting the strongest available 4G cell and the best‑performing core. Where 5G is present, policies can prefer 5G where it improves latency and stability.Q: How does this work across regions like Western Europe and North America?A: Regional eSIMs such as Esim Western Europe and Esim North America include multi‑MNO access in each country, enabling the same smart switching behaviour as you cross borders.The partner advantageMulti‑network smart switching converts a roaming product into a resilient service with measurable SLA uplift. It protects travellers from localised outages, evening congestion and poor peering, while reducing your support burden. With clear SLA targets, a simple policy, and disciplined measurement, you can prove value fast—and price accordingly.Next step: Explore packaging, SLAs and co‑marketing materials in our Partner Hub. If you’d like to discuss enterprise rollouts, visit For Business.

30 Oct 2025