Keeping a backup eSIM while travelling

Usually it does not need to be large, because the purpose is to get you back online while the main line is down, not to carry sustained heavy use. What deserves more attention than the allowance is validity that spans the whole trip, and a country list matching your route. If you are unsure what size suits your travel, send us the trip details on LINE or by email before buying.

Install it but leave the line switched off, so the phone does not switch to it unintentionally and so you control when the plan starts working. The caveat is that validity triggers differ between plans — some start at the first network connection — so read the detail on the one you chose before deciding when to test it.

That cannot be promised. Which network a plan uses in a given country depends on that supplier's arrangements, and it may be the same one your main line is on. If avoiding a local network problem is your only reason for buying a backup, understand up front that it may not work. For the other failures — running out of data, a plan expiring — a backup helps directly.

No — the profile is inside the phone that is gone. What helps there is a genuinely separate device, plus contact details kept outside the phone: on paper in another bag, or in an account you can reach from someone else's computer. Plan for the two risks separately, because they are different problems needing different preparation.

It depends on that plan's validity and terms. Most plans have a validity period, after which any remaining allowance can no longer be used, and the terms differ from plan to plan. The correct approach is to read the detail for the plan you hold; if it is still unclear, send us the order details and we will check it against the plan's actual terms.

Many people still do, because banks and other important services tie verification to the original number. A data backup cannot replace that if the plan has no number for receiving messages. The better move is to shift verification onto an authenticator app before you travel, then decide whether to keep the home number active — and check the roaming rates with your own operator either way.