Last updated: 15 October 2026

Monzo Mobile is a SIM-only phone plan sold inside the Monzo banking app. It costs £8, £12 or £20 a month, runs on O2’s network, and promises to get cheaper the longer you stay.

Most coverage stops at the headline prices. This review looks at the parts that matter once you sign up: how the loyalty discount really adds up, how it compares with giffgaff on the same network, and what it means to have your phone contract tied to your bank account.

Table of contents

• Monzo Mobile at a glance
• Plans and prices
• The loyalty discount, worked out
• Monzo Mobile vs giffgaff (same network)
• The bank-account catch
• Roaming
• Pros and cons
• How to join
• What real users say
• Verdict
• FAQ

Monzo Mobile at a glance

Monzo announced the service on 28 May 2026 with a waitlist, and rolled it out to customers over the summer. It is what the industry calls an MVNO: Monzo sells the plan, but the signal comes from someone else’s masts.

Feature	Detail
Network	Virgin Media O2 (Monzo says “one of the UK’s leading networks”)
Coverage claim	99% of the UK
SIM type	eSIM only, no physical SIM
Contract	Monthly rolling, no minimum term, no exit fees
Who can join	UK residents aged 18+ with a Monzo personal account
Payment	Taken from your Monzo account each month
Loyalty discount	5% off after each year, up to 30% after 72 months
Complaints scheme	CISAS (Ofcom-approved), not the Financial Ombudsman

Plans and prices

There are three plans. All include unlimited UK calls and texts, 5G with no speed caps, hotspot use and WiFi calling. Monzo says there are no out-of-bundle charges: when an allowance runs out, data stops rather than adding to your bill.

Plan	Price a month	Roaming data included	Calls and texts abroad
10GB	£8	None (add-ons only)	None
30GB	£12	10GB in Zone 1 (EU + Turkey)	60 minutes, 60 texts
Unlimited (600GB fair use)	£20	25GB in Zones 1 and 2	60 minutes, 60 texts

The full list, including the roaming zones, is on Monzo’s plans and pricing page. You can switch between plans in the app, and Monzo says changing plan does not reset your loyalty discount.

The loyalty discount, worked out

The selling point is a price that falls each year you stay. Monzo’s help page sets out the rule: nothing in your first 12 months, then 5% off your plan’s base price after each anniversary, reaching 30% after 72 months.

The discount is a flat 5 points of the base price each year, not 5% off the previous year’s price. That is why it reaches exactly 30% after six years, and why the Unlimited plan bottoms out at £14, not lower.

Year on Monzo Mobile	Discount	10GB	30GB	Unlimited
Year 1	0%	£8.00	£12.00	£20.00
Year 2	5%	£7.60	£11.40	£19.00
Year 3	10%	£7.20	£10.80	£18.00
Year 4	15%	£6.80	£10.20	£17.00
Year 5	20%	£6.40	£9.60	£16.00
Year 6	25%	£6.00	£9.00	£15.00
Year 7 onwards	30%	£5.60	£8.40	£14.00
Saved over first 6 years		£72	£108	£180

So the reward is slow. On the Unlimited plan you save nothing in year one and £12 in year two. The big savings only arrive if you stay for five years or more.

Two things can undo it. Cancelling and rejoining resets the discount to zero. And Monzo can change plan prices with 30 days’ notice; it says it has no plans to, and that your discount would still apply to any new price.

Monzo Mobile vs giffgaff (same network)

giffgaff also runs on O2, so it is the fairest comparison: same masts, similar coverage. These are giffgaff’s monthly rolling plans, which like Monzo’s have no contract, as listed on 15 October 2026.

Monzo Mobile	Monthly price	Closest giffgaff rolling plan	Monthly price
10GB	£8	5GB / 20GB	£8 / £10
30GB	£12	26GB / 50GB	£12 / £15
Unlimited	£20	Unlimited	£35

Monzo’s clearest win is unlimited data: £20 against £35 on a giffgaff rolling plan, or £25 on giffgaff’s 18-month contract. Over a year that is £180 less than giffgaff’s rolling unlimited plan, before any loyalty discount.

At the low end it is closer. If 10GB is plenty, Monzo’s £8 beats giffgaff’s £8 for 5GB, but giffgaff’s £10 buys double the data. giffgaff also runs bonus-data offers on its contract plans, so check both on the day.

The bank-account catch

This is the part most reviews skip. Monzo Mobile is not a standalone phone plan. It is a feature of your Monzo current account, and that has knock-on effects.

• You must keep the account. Monzo says you need to keep your Monzo current account open to keep the plan. To close the account, you first have to sort out the mobile plan; the app takes you through it.
• Payment only comes from Monzo. There is no direct debit from another bank and no card payment. If your Monzo balance is short, Monzo retries over the next few days and keeps your service running in the meantime, so you need to keep enough money in that account.
• No card rewards on the bill. You can’t put the bill on a cashback or points credit card. On a 1% cashback card, £240 a year of phone bills would earn £2.40, so the loss is small, but it is there.
• Personal accounts only. Monzo Business customers can’t use it, and you can only take out a plan for yourself.
• Complaints go to a telecoms scheme. Your bank complaints go to the Financial Ombudsman, but phone complaints go to CISAS, the Ofcom-approved scheme. You can refer a complaint to CISAS after six weeks, or sooner with a deadlock letter.

Monzo’s help pages don’t say what happens to your phone plan if Monzo itself closes or restricts your bank account. If that worries you, ask Monzo in the app before you port your main number.

If you are weighing up which banks and fees are worth keeping, our guide to avoiding UK bank fees covers the other costs to check.

Roaming

Roaming is separate from your UK data. Zone 1 covers 34 countries and territories (the EU plus places such as Norway, Switzerland, Iceland and Turkey). Zone 2 covers 20 more, including the US, Canada, Australia and Japan, but only on the Unlimited plan.

The 10GB plan includes no roaming at all. You would need to upgrade or buy an add-on (1GB to 20GB), priced in the app before you buy. Gaps include India, China and much of Latin America and Africa, so frequent long-haul travellers should check the country list first.

Pros and cons

Pros

• Unlimited data for £20 a month, £15 less than giffgaff’s rolling unlimited plan on the same network
• No contract, no exit fees and no out-of-bundle charges
• Price falls to 30% off after six years, and changing plan keeps your discount
• Run an eSIM alongside your current SIM to test the signal before porting your number
• Free PAC and STAC codes by text or in the app

Cons

• You must hold, and keep, a Monzo personal account
• No discount at all in year one, and it resets if you leave and come back
• eSIM only; some older Pixel, Samsung S20 and several Motorola and Xiaomi models are flagged as having issues
• 10GB plan has no roaming, and Zone 2 is Unlimited-only
• Bill can only be paid from your Monzo balance

How to join

1. Open a Monzo personal account if you don’t have one (you must be 18+ and live in the UK).
2. Check your phone is unlocked and supports eSIM. Monzo checks this during sign-up.
3. Pick a plan in the app. The first payment is taken that day, then on the same date each month.
4. To keep your number, text PAC to 65075 from your old phone and enter the code in the app. Monzo says most transfers complete the next working day.

You can cancel within 14 days for a full refund. After that, cancelling takes effect at the end of your billing month.

What real users say

Monzo has a TrustScore of 4.6 out of 5 on Trustpilot from more than 73,000 reviews, with 82% rating it five stars and 10% one star. Those reviews are about Monzo as a bank; we found none that discuss Monzo Mobile itself yet.

Verdict

If you already bank with Monzo and use a lot of data, Monzo Mobile is hard to beat: £20 for unlimited data on O2’s network, with no contract. The loyalty discount is a slow-burning bonus rather than a reason to switch on its own.

If you only need a few gigabytes, or you don’t want your phone tied to a bank account, giffgaff on the same network is just as good and gives you more freedom. Test it first with a second eSIM before you move your number.

For more on how digital banks are expanding beyond banking, see the rise of neo banks. And if you pay bills on a rewards card, our look at Lloyds Ultra cashback after year one shows how much card rewards are really worth.

FAQ

Which network does Monzo Mobile use?

It runs on Virgin Media O2’s network, the same one used by giffgaff. Monzo itself describes it as one of the UK’s leading networks with 99% coverage.

Do I need a Monzo account for Monzo Mobile?

Yes. You need a Monzo personal account, the bill is paid from it, and you must keep the account open to keep your plan. Business accounts aren’t eligible.

How does the Monzo Mobile loyalty discount work?

After your first 12 months you get 5% off your plan’s base price, rising by 5 points each year to 30% after 72 months. Changing plan keeps it; cancelling and rejoining resets it to zero.

Is Monzo Mobile better than giffgaff?

For unlimited data, yes on price: £20 a month against £35 on giffgaff’s rolling plan. For small allowances, giffgaff is similar or better value, and it doesn’t require a bank account.

Can I use Monzo Mobile abroad?

The 30GB plan includes 10GB in the EU and Turkey, and Unlimited adds 25GB across both zones, including the US. The 10GB plan needs a paid add-on to work abroad.

How do I complain about Monzo Mobile?

Complain in the app first. If it isn’t resolved within six weeks, or you get a deadlock letter, you can take it free to CISAS, the Ofcom-approved dispute scheme.

Sources: Monzo Mobile; Monzo help pages on plans and pricing, the loyalty discount, joining, cancelling, bills and payments, roaming, phone compatibility and complaints; giffgaff SIM-only plans; Telecoms.com, 28 May 2026; Trustpilot. All checked 15 October 2026.