eSIM Not Working? The Fix List That Solves 90% of Cases

eSIM faults look dramatic ("No Service" in a foreign country) but have boring causes. Run this list top to bottom — it's ordered by how often each fix works.

1. Data roaming is off on the travel line (the #1 cause)

Travel eSIMs connect by roaming onto partner networks — roaming must be ON for the travel eSIM. iPhone: Settings → Cellular → [travel line] → Data Roaming. Android: SIM settings → your eSIM → Data roaming. (Keep it OFF on your home SIM — that one's the bill-shock line.)

2. The wrong line is set for mobile data

Your phone may still be routing data through your home SIM. iPhone: Settings → Cellular → Cellular Data → select the travel eSIM. Android: SIM manager → Mobile data → travel eSIM.

3. Force a network re-registration

Airplane mode on, count to ten, off. If that fails: Settings → network selection → turn off automatic and pick a partner network manually, wait for registration, then set it back to automatic. This clears the majority of arrival-day "stuck" states.

4. Check the APN

Most eSIM profiles configure their APN automatically; a few need it typed manually. Compare the APN in your provider's install email against Settings → Cellular/Mobile → your eSIM → APN, character for character.

5. Is the plan actually active?

Check your plan dashboard: has validity started? Data remaining? Some plans activate on first network connection, others at purchase time — a plan bought a month ago on an activate-at-purchase basis may already be expired.

6. The locked-phone problem

A carrier-locked phone installs the eSIM but refuses to connect it. If every fix above fails and the phone came from a carrier contract, call them about unlock status — nothing else on this list will help until it's unlocked.

7. Restart, then reinstall — in that order

Restart the phone (fixes more than anyone admits). Only delete and reinstall the eSIM profile as a last resort after contacting support — many travel eSIM QR codes are single-use, and support can issue a fresh one.

Prevention beats all of it

Install at home on Wi-Fi, verify the profile appears, set the data line, flip the two roaming switches — then fly. Two minutes of setup removes every airport variable. Start with a plan for Turkey, Greece or anywhere else you're headed.