Ask Adrian: How can I avoid massive roaming bills in the US?

I’m going to America for three weeks soon. My mobile operator is Three. What can I do to make sure I’m not charged an absolute fortune?

​— M Murphy

Answer

I’m assuming you’re bill pay. If so, and you want to use your own phone number on Three, you have two options, both of which require you to sign up in advance of the trip.

The first is a monthly fee of €20, which will give you 300 minutes of calls to and from Ireland and 1GB of data for the period.

Now, unless you hardly use any data at all (never check social media or Google Maps, barely use WhatsApp and so on), that won’t be enough for three weeks.

The alternative is to sign up for a daily add-on allowance of €3.99 per day for 1GB of data (per day). This also includes all of your calls to and from Ireland.

You can organise this either by dropping into a Three shop or by calling Three’s ‘Care’ service on 1913.

Obviously, that €3.99-per-day offer is generally more suitable to stays of a week or so — for your three weeks it will cost €83.79, a somewhat hefty sum.

There are some much cheaper alternatives, but they would only provide for data, as opposed to your 08X number. In other words, you could use WhatsApp and FaceTime and everything else to call or video call or text, but not the carrier-SMS messages attached to your 08X number, if that makes sense.

In fact, this is what I do when I go abroad to the US. I use the ‘eSim’ functionality of my phone (almost all main phones sold in Ireland over the last two years have this feature) and buy credit on a services such as GoMoWorld (which you download from the App Store or Google Play Store) or Revolut (from within the normal Revolut app). They generally charge between €10 and €25 for a few gigabytes of data, which is enough to cover casual use of your phone, including Google Maps, WhatsApp and social media.

But I’d strongly advise you to put some sort of plan in place.

Like other operators, Three’s default charge for those who just land in the US and switch their phone on to mobile data is €4.99 per megabyte — the equivalent of €4,999 (yes, four thousand) per gigabyte. To be fair, you’re given a warning once you hit €50, but that’s still a nasty shock. So I’d absolutely make some provision soon.

If you land there and find you forgot to do anything, don’t panic. There is generally lots of free wifi in the US. And you can buy tourist sim cards there from about $30 that will give you basic data connectivity.

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