Wi-Fi calling abroad, without roaming charges

• Roaming uses your SIM on a foreign network. It needs nothing set up, but calls are billed at your carrier's roaming or travel-pass rates.
• Carrier Wi-Fi Calling carries your own SIM number over Wi-Fi. Abroad it depends on your carrier: some bill calls home as domestic, others charge international rates or switch the feature off outside your home country. It also needs an active SIM in the phone.
• An internet calling service such as TwinPhone runs in a browser or the app over any Wi-Fi or data connection. No SIM is involved, and the price is set by the number you call, not by where you are.

Check your carrier's travel terms first: if Wi-Fi Calling home is included in your plan, use it. If it is not, or you are calling a country your plan does not cover, a calling service is usually the cheaper path.

1. Sign up at twin-phone.com with an email or Google account, on your laptop or phone.
2. Add credit from $10. Credit never expires, so what is left over waits for the next trip.
3. Install the iPhone or Android app if you want to call from your phone, or just use the browser on a laptop or tablet.
4. On arrival, connect to hotel, café or home Wi-Fi, or to a local SIM or eSIM with data, and dial numbers with their country code (+1 for the US and Canada).

The person you call answers on their ordinary phone and needs no app.

Calls to your own SIM number still go to your SIM and roam as before. If people at home need to reach you over Wi-Fi, rent a US or Canadian number from $3.19/month and give it to them: it rings in your browser or the iPhone app wherever you are, and answering costs $0.02/min from your balance. See receiving calls abroad without roaming.