Why is my bank code not arriving?

Why this happens at all

Your bank sends a code to your number. Your number lives on your home carrier's network. For that text to reach you abroad, your home line has to be registered on a network in the country you are standing in.

Three things can break that. You switched the line off to avoid roaming charges. The line is on, but the local network cannot carry it. Or the line is on and reachable, and the bank is refusing to send.

The first is the most common by a wide margin. People turn off the whole line rather than only data roaming, because the two switches sit next to each other and only one of them costs money.

Receiving an SMS is free or close to free almost everywhere. Data roaming is the expensive switch. Turning off the line to save money on data is like unplugging the fridge to save on the doorbell.

The 3G shutdown is the reason this got worse

Until recently, a home line abroad fell back to 2G or 3G for calls and texts. That fallback worked almost everywhere, because those networks were universal and roaming agreements for them were decades old.

Networks have now switched 2G and 3G off. Japan, Korea, Singapore and Australia went early. Most of Europe and North America has followed. Voice and SMS now need VoLTE, which is voice carried over the 4G data network.

VoLTE roaming needs a specific agreement between your carrier and the local one, and those agreements are still incomplete. Where one is missing, your home line simply shows No Service and there is nothing on the phone to change.

This is why a traveller who had no trouble in 2019 suddenly cannot receive a bank code in 2026. Nothing changed on their phone. The network underneath it was retired.

Set this up before you fly

Wifi calling is the fix that removes almost every branch of this tree, and it has to be switched on at home. Most carriers require an emergency service address on file before it activates, and many refuse to accept that registration from a foreign IP address.

Thirty seconds before your flight saves an hour in a hotel lobby. Turn wifi calling on, confirm the status bar shows it, and check that your emergency address is correct.

While you are there, move at least one account off SMS entirely. In app approval and authenticator codes both work with no mobile network at all, so they survive every version of this problem.

1. Switch wifi calling on for your home line while you are still at home, and confirm the status bar shows it.
2. Set your banking app to approve logins in the app rather than by text, or set up an authenticator.
3. Keep the home SIM in the phone with the line on and data roaming off, and put your data on the travel eSIM.
4. Write down the international number on the back of your card, so you can call the bank over an internet call if you need to.