Before you begin
What you need to compare roaming and eSIM
Each network's day passes, per-megabyte rates and fair-use allowances are held in a source-attributed table and rechecked monthly, and the result also gives the eSIM price at which the two routes cost the same, so any quote you are shown can be judged against it without running the tool again.
Choose the exact current plan where it is listed. Published allowances for the named Three, 48 and GoMo plans are applied automatically; use the another-plan route if the label does not match your contract.
A provider quote is the strongest input. It replaces the built-in rate and lets the tool handle an unlisted plan or destination without guessing.
Use the final price, data allowance and activation validity of one eSIM package that is available for your destination.
Estimate data for the whole trip, not per day. Video and hotspot use can move the answer quickly.
Reading the answer
Understanding which option is cheaper for your trip
The cheaper route is recommended only when it supplies enough data for enough days and the phone can actually use it.
The break-even eSIM price is the most you could pay before the modelled Irish-network route becomes cheaper.
A small saving may not justify changing SIM settings if your Irish plan also includes calls and texts that the eSIM does not.
Common questions
Common roaming and eSIM questions
Is roaming or a travel eSIM cheaper?
It hinges on your network, your destination, how long you stay and how much data you use. The calculator sets your own plan against the eSIM you have in mind and finds the price where they break even.
Get a result above and the full answer opens here.
Is mobile roaming free in the EU?
That rests on Roam Like Home and on your own plan's fair-use allowance. The calculator checks your trip against that allowance and prices anything over it.
Get a result above and the full answer opens here.
Is the UK still included in Irish mobile roaming plans?
It turns on your provider and your plan. The calculator applies your plan's UK allowance, or the one in your app, and prices your trip on it.
Get a result above and the full answer opens here.
Will a travel eSIM keep my Irish phone number?
Your handset and how you set up the two lines decide it. The result walks you through setting up both lines for your trip.
Get a result above and the full answer opens here.
Are travel eSIMs data-only?
It depends on the package: check whether the listing names calls, texts or a phone number. The calculator asks whether you need ordinary calls or SMS as well as data, and tells you how to cover them if the eSIM does not.
How much does roaming cost outside the EU on Three, Vodafone or eir?
It varies by network and by destination. The calculator works out your own network's cheapest published option for your days and data, and what an eSIM would have to cost to beat it.
Get a result above and the full answer opens here.
Why do I enter the eSIM price myself?
eSIM prices and packages change frequently and can be shown in another currency. Using the live final price and allowance you can buy now is more accurate than a stale price table and keeps the recommendation independent of any affiliate relationship.
Does an affiliate relationship change the result?
No. The calculator compares the published Irish tariff or your own provider quote with the eSIM quote you enter. A future commercial link can appear only after the result and cannot alter the calculation or recommendation.