How to Install an eSIM on iPhone and Android

You've got your QR code. You're staring at it. Maybe you're at the airport, maybe you're already abroad. Either way, you need data, and you need it now.

This guide walks you through installing your Slashtel eSIM on iPhone and Android. It covers the exact menu paths, the common errors, and what to do when things go wrong. No fluff.

Before you start: WiFi, battery, don't delete

Three things before you scan anything.

1. You need Wi-Fi. The eSIM downloads a profile to your phone. That uses data. If you're not on Wi-Fi, the installation will fail. Airport Wi-Fi works. Hotel Wi-Fi works. Your home Wi-Fi works. Just be connected.

2. Charge your phone. The installation takes two minutes, but if something goes wrong, you'll be troubleshooting. Don't do this at 5% battery. Plug in first.

3. Don't delete the QR code after installing. You might need it again. Some phones let you re-add a profile if you accidentally remove it. Save the email. Screenshot the QR code. You'll thank yourself later.

Also, check that your phone is unlocked. If you bought it through a carrier contract, it might be locked to that network. You can check in Settings > General > About on iPhone, or Settings > About Phone on Android. If it says "Carrier Lock: SIM locked", you need to contact your carrier before installing.

iPhone step-by-step (iOS 17/18)

The menu labels changed slightly in recent iOS versions, but the path is the same.

1. Open Settings. The grey gear icon. Not the Camera app, not the Photos app. Settings.

2. Tap Cellular. It's usually the third or fourth option down. On some iOS versions, it's called "Mobile Data" or "Mobile Service". Same thing.

3. Tap "Add Cellular Plan". It's a blue link near the top. On iOS 18, it might be under "Add eSIM" or a plus icon in the top right corner.

4. Scan the QR code. Your phone will open a camera viewfinder. Hold the QR code from your email in front of it. Don't use the regular Camera app — the built-in scanner in Settings is more reliable for this.

5. Wait for the profile to download. You'll see "Preparing your cellular plan" or similar. This takes 10-30 seconds. Don't close the screen.

6. Label the plan. When prompted, tap "Label" and choose "Other". Type "Slashtel". This makes it easy to identify later when you're managing your data lines.

7. Set your default line. If you have a primary SIM, iOS will ask which line to use for calls, messages, and data. Choose:

   • Default line for calls and messages: your primary SIM (so you keep your number)
   • Data line: Slashtel

8. Done. You'll see the Slashtel plan in your Cellular settings with a green "On" indicator.

If you're setting this up before travel, the plan will show "No Service" until you land. That's normal.

Android step-by-step (Samsung One UI, Pixel)

Android varies by manufacturer, but the core path is the same. Here's how it works on the two most common brands.

Samsung (One UI)

1. Open Settings. The gear icon.

2. Tap Connections. It's near the top, with a wifi symbol.

3. Tap SIM card manager. You'll see your current SIMs listed.

4. Tap "Add eSIM". It's a blue button near the bottom.

5. Scan the QR code. Samsung will open a scanner. Point it at the QR code from your email.

6. Wait for the profile to download. You'll see a progress bar. Don't interrupt it.

7. Name the plan. Samsung asks you to name each SIM. Type "Slashtel".

8. Choose your data SIM. After installation, tap "Mobile data" and select Slashtel. Your primary SIM stays for calls and texts.

Google Pixel (stock Android)

1. Open Settings. The gear icon.

2. Tap Network & internet.

3. Tap SIMs. You'll see your current SIMs.

4. Tap "Add SIM" or "Download a SIM instead". The wording varies by Android version.

5. Scan the QR code. Pixel opens a scanner. Point it at the QR code.

6. Wait for the profile to download. This takes 10-30 seconds.

7. Name the plan. Tap "Slashtel" when prompted.

8. Set it as your data SIM. Go back to Network & internet > SIMs, tap "Mobile data", and select Slashtel.

Label it 'Slashtel', set primary SIM for calls, eSIM for data, Data Roaming ON

This is the step most people skip, and it's why they end up confused later.

Label the plan. Both iOS and Android let you name your SIMs. Name the eSIM "Slashtel". Name your primary SIM whatever you want. When you're in Settings trying to figure out which line is which, you'll be glad you did.

Set the primary SIM for calls and texts. Your UK number stays on your primary SIM. Calls and messages route through that line. Your contacts won't notice any difference.

Set the eSIM for data. All mobile data routes through Slashtel. This is your internet connection.

Turn Data Roaming ON for the eSIM. This is the critical one. Your Slashtel eSIM connects to local networks when you travel. That requires Data Roaming to be enabled on the eSIM line. It does not incur extra charges — it's how the eSIM works.

Keep Data Roaming OFF on your primary SIM. This prevents your home carrier from charging you international roaming rates. You'll still receive calls and texts on your primary SIM, but your phone won't use data through it.

On iPhone: Settings > Cellular > tap the Slashtel plan > toggle "Data Roaming" on.

On Samsung: Settings > Connections > SIM card manager > tap the Slashtel SIM > toggle "Data roaming" on.

On Pixel: Settings > Network & internet > SIMs > tap the Slashtel SIM > toggle "Data roaming" on.

The 5 errors and fixes

1. "This code has already been used" or "Plan already installed"

You scanned the QR code twice. eSIM QR codes are single-use. If you see this error, check whether the plan is already on your phone.

On iPhone: Settings > Cellular. Look for a plan labelled "Slashtel" or "Personal". If it's there, you're done — you don't need to scan again.

On Android: Settings > Connections > SIM card manager (Samsung) or Settings > Network & internet > SIMs (Pixel). Same check.

If the plan is installed but not working, skip to error #3 below.

2. "Invalid QR code" or "Unable to activate"

Check that you're scanning the right QR code. Slashtel sends a single QR code in the confirmation email. Make sure you're scanning that one, not a screenshot of a different plan.

Also, use the built-in scanner in Settings, not the Camera app. The Camera app sometimes crops the QR code or adds a URL preview that interferes.

If it still fails, your phone might be carrier-locked. Check Settings > General > About on iPhone, or Settings > About Phone on Android. If it says "SIM locked", you need to contact your carrier.

3. No signal after landing

You installed the eSIM before travel. It showed "No Service" at home. You landed. Still "No Service".

Your eSIM activates when it first connects to a network at your destination. If it doesn't connect automatically, try these in order:

1. Turn your phone off and on again. This forces a network rescan.
2. Check Data Roaming is ON for the Slashtel line.
3. Manually select a network. On iPhone: Settings > Cellular > tap the Slashtel plan > Network Selection > turn off Automatic, then pick a network. On Android: Settings > Connections > SIM card manager > tap the Slashtel SIM > Network operators. Try a few — one will work.
4. Wait 5 minutes. Sometimes the network takes a moment to register your eSIM.

4. APN settings

Most eSIMs work without touching APN settings. If you have data but nothing loads, or you see a "No APN" error, you might need to set it manually.

On iPhone: Settings > Cellular > tap the Slashtel plan > Cellular Data Network. Enter:

• APN: slashtel
• Username: (leave blank)
• Password: (leave blank)

On Android: Settings > Connections > Mobile networks > Access Point Names (Samsung) or Settings > Network & internet > SIMs > Access Point Names (Pixel). Tap the plus icon and create a new APN with the same details above.

5. iMessage/WhatsApp confusion

You have data. You're online. But iMessage is sending green bubbles, or WhatsApp is asking you to verify your number.

iMessage: If you have a UK primary SIM, iMessage should work as normal. If you removed your primary SIM and only have the eSIM, iMessage has no number to associate with. Go to Settings > Messages > Send & Receive, and check that your Apple ID email is ticked. You'll still receive iMessages on your email address.

WhatsApp: WhatsApp is tied to your primary SIM's number, not your data connection. As long as your primary SIM stays in the phone, your WhatsApp number stays the same. If you removed your primary SIM, WhatsApp may ask you to verify your number. Reinsert your primary SIM and restart WhatsApp to fix this.

When to WhatsApp us

If you've gone through all the fixes above and you're still offline, contact us. We respond quickly.

Before you message, grab these three things:

1. Your EID. This is a unique identifier for your phone's eSIM hardware. On iPhone: Settings > General > About > EID. On Android: Settings > About Phone > EID or Settings > About Phone > Status > EID.

2. A screenshot of the error. If you're seeing an error message, screenshot it. If you're seeing "No Service", screenshot your Cellular or SIM settings screen.

3. Your order number. You'll find it in the confirmation email.

Send these to us on WhatsApp at +44 1234 567890 or email esim@slashtel.com. We'll check your plan, verify the profile, and get you sorted.

Most issues are resolved in minutes. If your eSIM is genuinely faulty, we'll replace it or refund you — whatever gets you online fastest.

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Related guides:

• Set up your UK eSIM before you fly
• Keep your Indian SIM active for OTPs
• Check eSIM compatibility with your phone