Last updated: 12 November 2026. Prices and features checked on honestmobile.com.
In this review
If you travel a lot, you know the feeling. You land, turn off aeroplane mode, and wonder if that first WhatsApp message just cost you a few pounds. Or your signal drops on the train and Google Maps freezes at the worst moment.
I have used Honest Mobile's Smart SIM as a back-up eSIM on my trips for about a year now. This review covers what it actually does, what it won't do, how it compares with roaming and Airalo, and whether £45 a year is worth it in 2026.
AT A GLANCE
My verdict
Worth it if you travel 2+ times a year or lose signal on your commute
Price
£45 a year (£3.75 a month) or £10 a month
UK networks
EE, O2, Three and Vodafone - you use whichever has signal
Abroad
190+ countries, no roaming charges
Data
Unlimited, but only on 500+ essential apps
Not included
Normal calls and texts, social media, streaming, video calls, VPNs
Safety net
14-day money-back guarantee
🛍️ BLACK FRIDAY 2026
Honest Mobile takes 20% off Smart SIM annual plans from 20 November to 1 December 2026. That brings the £45 plan down to about £36 for the year. Check the current Smart SIM price.
What is the Honest Mobile Smart SIM?
The Smart SIM is a data-only eSIM that sits next to your normal SIM. It does not replace your main plan. You keep your number, your contract and your network. The Smart SIM is there for the two moments your main SIM lets you down: no signal in the UK, and expensive roaming abroad.
In the UK, it can connect to EE, O2, Three or Vodafone. So if your network drops out on a train or a country road, you switch your data line to the Smart SIM and it uses whichever network has the best signal where you are.
Abroad, the same eSIM works in 190+ countries with no daily roaming fees. Honest Mobile has also rolled out "Smart SIM 2.0", which it says gives faster speeds.
The Smart SIM works on a list of 500+ essential apps (image: Honest Mobile)
Which apps work (and which don't)
To keep the price low, the data only works on a list of 500+ essential apps. Before you panic, the list covers almost everything I need on the move:
Messaging: WhatsApp (including WhatsApp calls), iMessage, Signal, Telegram
Maps: Google Maps, Apple Maps, Waze, Citymapper
Transport: Uber, Bolt, Trainline and airline apps
Banking: Monzo, Revolut, Starling, Wise and most big UK bank apps
Travel: Airbnb, Booking.com, Skyscanner
Other: Google Search, ChatGPT, translation and weather apps
What you can't do: scroll Instagram or TikTok, stream Netflix or YouTube, make video calls, or browse the open web. It is data only, so normal calls and texts stay on your main SIM. VPNs are not supported either, which matters if you work remotely on a company VPN.
For travel, I am fine with that. Hotel WiFi handles Instagram. The Smart SIM makes sure I can always message someone, get to where I need to go, and check my bank.
Smart SIM vs roaming vs Airalo
Here is how the three options compare for a typical UK traveller:
HONEST MOBILE SMART SIM
£45 a year. One setup, works in 190+ countries and on all four UK networks. Unlimited data on essential apps only. Best for frequent travellers who want maps, messages and banking everywhere.
NETWORK ROAMING (EE, VODAFONE, O2, THREE)
Uses your normal allowance, but most UK networks now charge a daily or weekly roaming fee, even in Europe, and more outside Europe. A week away can cost more than a year of Smart SIM. Best if you need full data and do not want a second eSIM.
AIRALO (DESTINATION ESIM)
You buy a data pack for each trip or region. Full data, so social media and streaming work. Best for a long trip to one place where you need lots of data. See Airalo plans.
I use a mix. The Smart SIM sits in the background all year. For a fortnight somewhere like Thailand where I want full data, I add an Airalo eSIM. And since I moved my main number to Monzo Mobile for its roaming allowance, I still keep the Smart SIM for the places Monzo does not cover, like India, Bali and a Doha connection. Revolut Mobile is another option if you want roaming built into your main plan.
Price: is £45 a year worth it?
Annual: £45 a year, which works out at £3.75 a month
Monthly: £10 a month, cancel any time
The annual plan is the obvious pick. It pays for itself in under five months against the monthly plan, and if you would otherwise pay a daily roaming fee, one long weekend abroad can cover most of it. I went straight for the annual plan and have not looked back.
💡 TIP
If you are buying in November, wait for the sale. From 20 November to 1 December 2026, annual plans are 20% off, so about £36 for the year. Earlier in 2026 Honest ran a 15% off sale, so it is worth checking for a deal before you pay full price.
My experience: setup and day-to-day use
Setup took about two minutes. You order on the Honest Mobile website, scan a QR code, and your iPhone or Android adds the eSIM. Then you download the Honest Mobile app to manage it.
When you need it, you switch your phone's mobile data line to the Smart SIM in settings. It takes a couple of taps and you are connected within moments. It is not automatic in the UK, so you need to remember to switch back when your main signal returns.
Where it has earned its money for me is the short layover: a night in a hub city where buying a separate eSIM feels like a faff, but I still need Maps, Uber, WhatsApp and my banking app the moment I land. It is also my fallback for UK not-spots on the train to Heathrow.
Trains and rural roads are where a back-up eSIM earns its keep (image: Honest Mobile)
Pros and cons
✅ PROS
One eSIM for 190+ countries, set up once
Uses all four UK networks for signal blackspots
Unlimited data on the apps that matter when travelling
£45 a year is cheaper than most roaming passes
14-day money-back guarantee
❌ CONS
Essential apps only - no social media, streaming or video calls
Data only, no normal calls or texts
No VPN support
eSIM only, so you need a compatible phone
You switch to it by hand
Who should get the Smart SIM?
It is a good fit if you take two or more trips abroad a year, often lose signal on your UK network, commute by train through patchy areas, or hate buying a new eSIM for every trip.
It is probably not for you if you need full data abroad for streaming or social media. In that case, a destination eSIM like Airalo or a main plan with good roaming will suit you better. If you are new to eSIMs, start with our guide on why every traveller should consider an eSIM.
Honest Mobile Smart SIM FAQ
Is Honest Mobile Smart SIM worth it?
For most frequent UK travellers, yes. At £45 a year it costs less than a week of daily roaming fees on many UK networks, and it also fixes UK signal blackspots by using EE, O2, Three and Vodafone. It is less useful if you mainly want social media and streaming abroad.
How much does the Honest Mobile Smart SIM cost?
£45 a year (about £3.75 a month) or £10 a month. From 20 November to 1 December 2026, annual plans are 20% off, so about £36 for the year.
Which networks does the Smart SIM use in the UK?
EE, O2, Three and Vodafone. It connects to the network with the best signal where you are.
How many countries does the Smart SIM work in?
More than 190 countries, with no roaming charges.
Can I use Instagram, Netflix or a VPN on the Smart SIM?
No. Data works on 500+ essential apps such as WhatsApp, Google Maps, Uber and banking apps. Social media, streaming, video calls and VPNs are not supported.
Does the Smart SIM replace my normal SIM?
No. It is a data-only eSIM that sits alongside your main SIM, so you keep your number and contract. Normal calls and texts stay on your main SIM.
Is there a money-back guarantee?
Yes. Honest Mobile offers a 14-day money-back guarantee.
The verdict
The Smart SIM has become one of those "why didn't I do this sooner?" products for me. Setup is quick, the app list covers what I need when travelling, and knowing I can always WhatsApp, navigate and reach my bank in 190+ countries is a real weight off. At £3.75 a month - or about £3 in the Black Friday sale - it is cheap insurance.
Get the Honest Mobile Smart SIM here. If it does not work for you, the 14-day money-back guarantee has you covered.
🧰 USEFUL TOOLS & GUIDES
Guides: Why every traveller should consider an eSIM · Monzo Mobile roaming · Revolut Mobile launch · All eSIM posts
Tools: Award Travel Finder · Flight Queue · Airport Lounge List · Flight Seatmap
Happy travels,
Jack
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