Cheapest way to keep a UK mobile number using an eSIM

Terence Eden — Sat, 11 Apr 2026 11:34:38 +0000

I have an old mobile phone number that I'd like to keep. I think it is registered with a bunch of services for 2FA by SMS, but I can't be sure. So I want to keep it for a couple of years just in case I need it to log on to something.

I don't want to faff around with physical SIMs, so I went looking for the cheapest way to keep my number for the longest time. There are a whole bunch of providers out there who will do low-cost monthly contracts (like Spusu), which I don't want. Similarly, there are some pure PAYG providers who require you to top-up with £10 every few months (like 1pmobile).

In the end, I went with Lyca Mobile (affiliate link). Total cost was £10 which should last indefinitely.

The process isn't particularly straightforward. Here's how it works:

First, add a PAYG SIM to your basket and select "eSIM"

Next, click the Bin icon (🗑) in the top right. You'll get this pop-up:

Select "Discard plan & add credit" - you'll return to this screen:

The minimum top-up is a tenner, so select that. From there, you can add details of your old number, its porting code, and when you want the port to take place. Then pay.

Done! You'll receive your eSIM instantly. Scan it with your phone and you'll be up and running. The phone number porting will take as long as it takes.

OK, but will Lyca let you keep a number indefinitely? Here's what they say:

How long can I keep my number for if I don’t use any of Lyca Mobile’s services?

Normally we will keep your number for 120 days if you do not use our service. However, you may also keep your Lycamobile number for up to 1 year without using our service. Just dial *139*9999# from your Lycamobile and follow the instructions on the screen. Please be aware that there will be a fixed annual fee of £15 which will be deducted from your balance.

Source

Note, their chatbot says the fixed fee is a fiver. Like all half-baked AI systems, it is wrong.

So, what does "using" consist of? This is hard to find out! I think is any chargeable event. Based on their current PAYG pricing the cheapest options are:

Send an SMS for 23p
Use 1MB of data for 15p.

If I'm right, you could use 1MB of data every 120 days. That would deplete your credit in about 22 years. More than long enough for me!

There you have it, I'm pretty sure that's the cheapest way to keep a UK mobile number on an eSIM. You can keep it switched off for 119 days, flick it on, send a quick message, then shut it down again.

Click the referral link to join Lyca Mobile

Review: Roamless Travel eSIM ★★★★★

Terence Eden — Wed, 08 Jan 2025 12:34:56 +0000

I've got a bunch of travel coming up to exotic locations. Previously, I've bought a local SIM card when I've landed - but they're often expensive, fiddly to fit, and queuing in an airport isn't much fun. I've also bought pre-paid SIMs which have a fixed amount of data or only last a specific amount of time.

But the big problem with those solutions is that you lose a fair bit of value unless you exhaust the SIM. If you buy a month-long package but are only on holiday for a week, that's a waste. Similarly, if you buy 2GB of data but only use 500MB, you've wasted your money.

So I'm trying Roamless which is a PAYG eSIM.

The concept is pretty simple:

Stick $10 in your account.
Visit Ruritania on holiday for a week and use data which costs $1.25/GB
Come home.
Fly off to Utopia but use 50MB of data during your 2 hour transfer at Blefuscu airport ($2.50/GB)
During your fortnight in Utopia, visit Lilliput where your phone automatically roams to the local network ($1.50/GB)

And so on. The credit in your wallet decreases with use; not with time. You aren't forced to buy multi-GB bundles which you can't use. Coverage is worldwide, so you don't need to spend time looking for a local SIM.

The Good

It works! I signed up, paid my money, installed the Android app, and my eSIM installed itself. When I landed in Morocco, my phone seamlessly connected to the local network.

I spent a week on holiday and paid a couple of dollars for half a gigabyte of data. I think that's pretty reasonable.

Turns out most of the places I went had WiFi, so buying a dedicated SIM with a few GB of data just for Morocco would have been a waste of money.

Speeds seemed fine. I connected to a couple of different Moroccan networks on 3G and 4G - I don't think there's 5G in Marrakesh. I didn't run any speed-tests, but for maps, a bit of photo-sharing, and Signal/WhatsApp calls it did the trick.

As well as data, you can use your credit to make local phone calls. I don't think I'd make much use of the feature - but it is good to know it exists.

The Bad

Data costs are reasonable, but not the cheapest. You will inevitably find a better per/GB deal if you buy a local SIM with an inclusive data bundle. If you know you're going to be somewhere for a week and you're sure you'll use all the data, it might make sense to use a different product.

Costs are in US$ - so you'll need a card with low/no foreign exchange fees to get the most value for money.

As with any roaming connection, latency is increased vs using a local SIM. My IP address placed me in Belgium. That didn't cause any problems, but you probably don't want to play games which require a low ping.

The SIM will roam anywhere - even your home country. You'll need to either disable the eSIM or switch off roaming when you're at home. But, on the plus side, UK prices aren't too expensive.

There's no inbound calling to the SIM. If you're going to places which require a local number, you might find it convenient to pick up a local SIM to get a temporary number.

The App

The app isn't mandatory. You can install the eSIM via a QR code as per normal. But you'll need to use the app if you want to take advantage of any of the discount / referral codes. The app steps you through setting up the eSIM which is useful if you've never used it before.

The app itself is a bit bare-bones and doesn't look great. But it is the sort of thing you'll go into once to set up and then never again, unless you need to top up.

It will show you how much you've used and what your balance is.

The app has a VoIP client, so you can make local calls when roaming. Again, the prices aren't the cheapest per minute - but they come out of your credit and you aren't forced to buy a calling bundle.

Oh, and as a nice feature, when you return home - it reminds you to turn it off.

Not many apps will tell you to spend less money with them!

Verdict

Roamless takes all the hassle out of roaming through multiple countries.

If you're the sort of person who goes to one place for a set period of time, you'll almost always be better off buying a local SIM. But if you flit between countries and don't want to spend the entire journey on your phone, Roamless will suit you just fine.

There are no gimmicks or upsells - you get PAYG data which you can use anywhere.

The Obligatory Referral Link

If you use code TERENCEN3R, we both get a $3 bonus.

eSIM – Terence Eden’s Blog