How TadiSim Works — 60-Second Setup Guide

Honestly, it's three steps

We know every eSIM company says "easy setup." But with TadiSim, it really is just: 

  • Buy it
  • Check your email
  • Scan the QR code

The whole thing takes about a minute. Maybe two if you're on airport WiFi that barely works.

Here's the slightly more detailed version so you know exactly what to expect.

Navigating to Add Cellular Plan in iOS 18 settings for Vietnam eSIM setup

Step 1: Buy your plan

Pick the number of days you need. We currently offer 10-day and 20-day plans, both with a real Vietnamese +84 phone number included.

  • 10 Days: 6GB high-speed data per day, 100 free local minutes, 100 free SMS
  • 20 Days: 5GB high-speed data per day, 100 free local minutes, 100 free SMS

Add to cart, checkout securely. We accept major credit cards, PayPal, Apple Pay, and Google Pay. Prices are in USD but your card will handle the conversion.

Important: Make sure your email address is correct. This is where we send your eSIM. If you typo your email, we can't help you — we don't know where to send it.

Step 2: Check your email (within 60 seconds)

You'll get two emails from us:

  • Order confirmation — "Yep, we got your money."
  • eSIM delivery — This has your QR code, installation steps, and a PDF backup in case the QR code gives you trouble.

If you don't see the second email within 5 minutes, check your spam or promotions folder. Still nothing? Email us at Support@tadisim.com and we'll resend it manually.

Pro tip: Screenshot the QR code as soon as you open the email. If your hotel WiFi is terrible and the email won't load later, you'll still have the image.

Step 3: Scan and activate

On iPhone (XR/XS or newer):

Scanning TadiSim QR code to install Vietnam eSIM on iPhone
  • Open Settings → Cellular → Add Cellular Plan
  • Point your camera at the QR code in the email
  • Label it "TadiSim" or "Vietnam" so you don't confuse it with your home plan
  • Keep your home SIM as "Primary" and set TadiSim as "Secondary" for data
  • Turn on Data Roaming for the TadiSim line (this is safe — you're not roaming, you're on a local Vietnamese plan, but iOS calls it roaming anyway)

On Android (Samsung S20+, Pixel 3+, etc.):

Opening SIM card manager on Samsung Android to add a new mobile plan
  • Open Settings → Connections → SIM card manager → Add mobile plan
Scanning Vietnam eSIM QR code on Android device to activate TadiSim
  • Scan the QR code 
Android status bar showing Viettel 4G signal after successful TadiSim eSIM activation
  • Follow the prompts. Different Android skins (Samsung One UI, Xiaomi MIUI, etc.) word this slightly differently, but it's always under SIM or Network settings.

When to activate:

  • You can scan the QR code before you fly. The plan only starts counting days when you actually turn it on in Vietnam.
  • Or scan it when you land. Either works.

The two things that trip people up (read this)

1. Your phone MUST be carrier-unlocked

If you bought your iPhone through AT&T, Verizon, T-Mobile, or most UK carriers on a contract, it might be locked. A locked phone rejects any SIM or eSIM that isn't from that carrier.

How to check:

  • iPhone: Settings → General → About → look for "Carrier Lock." It should say "No SIM restrictions."
  • Android: Settings → About Phone → Status → SIM status. Look for "Network" — if it says anything about a specific carrier lock, you're stuck.

If your phone is locked, no eSIM in the world will work, including ours. You need to get it unlocked by your carrier first. Usually takes 24-48 hours if you've paid off the contract.

2. Your phone MUST support eSIM

Most phones from 2020 onwards do, but not all. Here's the quick list:

  • iPhone: XR, XS, 11, 12, 13, 14, 15, 16 series (all models). iPhone SE (2nd gen and newer).
  • Samsung: S20, S21, S22, S23, S24 series. Note 20 series. Z Flip and Z Fold series. Some A-series models.
  • Google: Pixel 3 and newer.
  • Others: Most newer Motorola, Huawei flagship, and Xiaomi flagship models.

Not sure? Email us your exact phone model (e.g., "iPhone 14 Pro Max from Verizon") and we'll tell you in 10 minutes whether it'll work.

What happens after activation

  • Data: You should see "Viettel" or "Vinaphone" in your status bar within 30 seconds of turning it on. 4G or 5G icon should appear.
  • Phone number: Your +84 number is printed in the same email as the QR code. Write it down. You'll need it for Grab, hotel check-ins, and food delivery.
  • Calls & SMS: The 100 free minutes and 100 free SMS work between TadiSim numbers. If your travel buddy also has a TadiSim, you can call and text each other without using data.
  • Hotspot: Yes, it works. Turn on Personal Hotspot in your settings and your laptop/tablet can connect. The data comes out of your daily allowance.

If something doesn't work

Don't panic. 99% of "it's not working" issues are one of three things:

  • Data Roaming is turned off for the TadiSim line. iPhone users miss this constantly.
  • The phone is still trying to use your home SIM for data. Go to Settings → Cellular/Mobile Data and make sure TadiSim is selected as the active data line.
  • You're in a building with thick walls. Step outside. Vietnamese concrete is excellent for many things. Phone signal is not one of them.

Still stuck? Email us. Include your phone model, iOS/Android version, and what you see on your screen. We'll sort it out.