Roaming bills or a family pool: what changes when everyone has their own SIM

Most families travel on whatever their phone contracts allow. Some contracts include roaming in certain countries. Others charge a daily fee whenever the phone uses data abroad, or charge by the megabyte outside a set list of destinations. The terms differ by network, by contract and by country, and they change more often than anyone rereads them.

In a household with four or five contracts, that means four or five sets of terms. A teenager's contract may be on a different tariff from yours. A grandparent's may have no roaming allowance at all.

The problem is timing

Roaming charges show up after the holiday. You find out what the data cost when the bills arrive, spread across several accounts, and by then there is nothing left to decide.

On tariffs with a daily roaming charge, that charge can also be triggered by accident. A phone that checks email as the plane lands, or an app refreshing in the background, can use data before anyone has chosen to.

What a family pool changes

With PERDIEM, one parent holds a prepaid family pool of credit. You add the people who are travelling, and for each person you pick a destination and a data plan. The price is shown before you confirm, and it is drawn from the pool when you do. Each person ends up with their own SIM, on their own phone.

So the cost of the trip's data is known before you leave, not after you get home. It sits in one place rather than across several accounts. There is no subscription and no stored card. Credit in the pool does not expire, so whatever is left after one trip is there for the next.

Limits for each person

Because each person is a separate member, you can set a spending limit for each of them and choose which countries they can use. The limit is a ceiling on what can be drawn from the pool for that person. The country choice stops a SIM being set up for somewhere they are not going.

None of this watches anyone. PERDIEM does not track location and does not show a live view of each person's data use. It records what was bought, for whom, and what it cost.

If something goes wrong

Occasionally the connectivity provider cannot issue a SIM after the pool has already been charged. When that happens, the money goes back into the pool automatically. You do not have to notice it, write in or ask.

What does not change

Plans are data only. A PERDIEM SIM does not come with a phone number, so it will not make ordinary calls or send texts. Your home line stays on the phone for those, and your home network's roaming terms still apply to any calls and texts you make or receive abroad.

Each phone still has to support eSIM and be unlocked. Plans come from a connectivity provider's catalogue and vary by country, so what is on offer for one destination may differ from the next. And when a plan runs out, you get that person another one from the console, drawn from the pool in the same way.

The change is modest, and useful. You decide what the trip's data costs before you go, and nobody opens a bill they were not expecting when you get back.