What is data roaming?

Data roaming is your home carrier letting the phone use another country's network, billed by your carrier at its own rates. It is convenient and, without a pass, expensive. With a travel eSIM the same switch has two sides: off for your own SIM so it does not bill you, on for the eSIM so it can pass data.

What a day of roaming costs

Prices read on the carriers' own pages, with the date. A day pass is charged for every day the phone touches data abroad, whether you use 20 MB or the whole allowance.

Home carrierPassPriceTwo weeksChecked
Telstra (Australia) International Day Pass
2 GB a day, Zone 2–3 (Asia, Europe, Americas)
A$10 a day A$140 2026-09-05
AT&T (United States) International Day Pass
per line, per day used abroad
$12 a day $168 2026-09-05
Rogers (Canada) International Travel Pass, 14 days
180+ destinations
C$100 for 14 days C$100 2026-09-05

Every price above links to the carrier's own page, so you can check it against your plan — passes differ by tariff and by zone. Switched roaming on and still no data? The six checks.

The two switches that matter

iPhone Settings → Cellular → tap each line. Your own SIM: Data Roaming off. The travel eSIM: Data Roaming on, and set it as the line for Cellular Data.
Android Settings → Network & internet (or Connections) → SIMs → tap each line. Your own SIM: Data roaming off. The travel eSIM: Data roaming on, and choose it for Mobile data.
Before you fly Install the eSIM at home over Wi-Fi and leave it off. Switch it on after landing; the validity clock starts at the first connection.

When roaming is still the right choice

A one-day stopover, a phone without eSIM, or a plan that already includes the country at no extra cost. For anything longer, a travel eSIM for the destination costs less than the pass and keeps your number working through your own SIM.

Rules of the country

Roaming and eSIM both meet whatever the destination requires: an identity check, a handset registry, an APN typed by hand. The rules section reads them from the primary documents, country by country.

Common questions

toggle_on Should data roaming be on or off?

Off for your own SIM, so it does not bill you by the megabyte or the day. On for the travel eSIM: that profile is registered abroad by design and needs roaming enabled to pass data. The two switches live in the same Settings screen, one per line.

payments Does data roaming cost money?

Yes, unless your plan includes the country. Most carriers sell a day pass, charged for every day the phone uses data abroad; without a pass, pay-as-you-go rates apply. The prices above are read from the carriers' own pages with the date.

sim_card Will a travel eSIM work if data roaming is off?

No. The eSIM profile comes from a network partner, and the phone treats it as a roaming line. Switch data roaming on for the eSIM line only; leave it off for your own SIM.

flight_takeoff Does airplane mode stop roaming charges?

Airplane mode cuts every radio, so yes, but it also cuts calls, texts and the eSIM. The precise tool is the per-line data roaming switch: off for your SIM, on for the eSIM, and Wi-Fi calling for calls home if your carrier supports it.

call Can I keep receiving calls and texts with roaming off?

Data roaming off stops data only. Calls and SMS over your own SIM still arrive and are billed at your carrier's roaming rates for voice and messages, which are usually far lower than data. Calls over WhatsApp or FaceTime use the eSIM data and cost nothing extra.