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Challenger and mobile banks

Find out how the new wave of digital banks, such as Monzo, Starling and Revolut, are aiming to shake up the banking sector

In this article
What is a challenger bank or mobile bank? Challenger banks and mobile banks: the benefits Starling Bank review Monzo Bank review Atom Bank review
Tandem Bank review How safe are e-money firms? Revolut review Monese review Nimbl review

What is a challenger bank or mobile bank?

The new wave of startup companies on the banking scene can't be found on the high-street - they're in your pocket. 

Buoyed by relaxed regulation and the growing shift of people using their phones to do their banking, these branchless, mobile-only banks are seeking to win customers from their more established rivals.

The term challenger bank is used to describe any bank that’s looking to challenge the big four in Britain: Barclays, Lloyds Banking Group (which includes Halifax, Lloyds Bank and Bank of Scotland), HSBC and RBS (which includes NatWest and Ulster Bank).

Established players, such as TSB, Virgin Money and Metro Bank, fall into this bracket, but for the purposes of this guide we’ll be looking to shine a light on the upstarts that offer mobile-only, branchless banking. 


Challenger banks and mobile banks: the benefits

The new banks we've analysed focus on modern design, personalisation, low fees and snappy customer service to tempt people in. 

They also feature real-time payment notifications, meaning you receive an alert every time there is some activity on your account. This not only make it easier to keep track of your spending, but you can also immediately spot if someone's using your account fraudulently. 

Most shy away from offering significant interest on current account balances or up-front incentives to switch.

Their future will lie in your willingness to share your spending data with businesses that have partnered with these new banks, receiving deals based on your spending patterns and behaviour.

How safe are challenger banks?

Startups are at greater risk of failing, so make sure you know how your money is protected.

The first to fall was Loot - a  digital current account geared towards students - which launched in 2014 and gained 212,000 users. Even a £2m investment from Royal Bank of Scotland couldn't save it from going into administration on 22 May 2019.

Loot wasn't covered by the Financial Services Compensation Scheme but e-money rules meant that customer money was ring-fenced - in this case it was protected and held by Wirecard Card Solutions Limited, Loot's card issuer.

Not all failures involve banks going bust. German bank N26 pulled out of the UK on 15 April 2020, having launched a beta version of its current account to UK customers in October 2018, due to our exit from the EU.

Starling Bank review

Starling Bank received a banking licence in July 2016, and launched the UK's first app-only current account in March 2017.

It has now opened 1.25 million accounts, including more than 100,000 small business accounts.

The London-based firm has built its IT systems from the ground up, raising £323m in funding to date - including £100m from an independent fund for boosting competition in banking plus investment from hedge fund manager Harald McPike, Merian Global Investors and Merian Chrysalis. 

Following our latest survey of the general public, Starling is a Which? Recommended Provider for current accounts with an impressive customer score of 83%. 


What does Starling Bank offer?


Starling offers a full personal, joint, and business current account allowing you to set up direct debits and standing orders.

You get instant notifications to your phone when you spend, and there are no fees for overseas spending or cash withdrawals. The app also automatically organises your spending by retailer and category (food, travel, entertainment and bills etc). 

Starling customers can deposit and withdraw cash at any Post Office branch. The debit card is compatible with Apple and Google Pay

The bank offers an additional 'Connected' debit card, aimed at people in self-isolation or living with disabilities. The card can be topped up by no more than £200 and given to friends and family who are doing shopping for you. 

Starling originally paid interest on current account at a maximum rate of 0.5% AER on balances up to £2,000. Since then, the rate has fallen to 0.05%. 

An overdraft of up to £5,000 is available, charged at 25% or 35% EAR, dependent on your credit score.  

You can also get a personal loan Starling - from a minimum £500 up to £5,000 - with rates ranging between 11.5% APR and 14.5% APR. 


What is the Starling Bank Marketplace?


Starling Bank Marketplace allows you to sync up your bank account with third party services so that you can manage all of your financial products in one place:

  • Anorak - life and income protection insurer
  • Churchill - home insurer, underwritten by UK Insurance Limited
  • CreditLadder - a unique service that reports your rent payments to Experian so that they count towards your credit history.
  • Flux - digitises your receipts (at participating retailers) 
  • Habito - a digital mortgage broker
  • Moneybox - rounds up your debit card spending to the nearest £1 and adds the change to a stocks and shares Isa, or Junior Isa
  • Money Dashboard - connects all of your online accounts in one place
  • Moneyhub - financial management tool
  • Onedox - manage household bills
  • PensionBee - a digital pension provider
  • So-Sure - mobile phone insurer covering loss, theft and damage. 
  • Tail - for cashback and rewards from local retailers 
  • Wealthify - an online investment Isa firm
  • Wealthsimple - an online investment manager
  • Yolt - connects all of your online accounts in one place
  • Yoyo Wallet - for points and rewards when you shop at participating retailers 

Where you are connecting your current accounts and savings e.g. with apps such as Money Dashboard and Yolt, ask the provider exactly how it is accessing your banking data.

Apps may use a combination of both open banking APIs (where you don't need to share your account login details) and screen scraping (where you must share your login details either with the app itself or a third party e.g. Yodlee). 


How do I open a Starling Bank current account?


There's no waiting list anymore. Once you've downloaded the Starling app from the official Android or iPhone app store to your smartphone, setting up an account will take less than five minutes.  

You'll be asked to pop in a one-time verification code (sent by text to your phone) and tell the bank your name, date of birth, email address and current home address. 

Next, you'll be asked to record a short video of yourself saying a simple phrase and supply a photo of your passport or driving licence.

Starling will then send your new debit card through the post within 2-3 business days.

You can chat to the bank on its app, via email, desktop live chat or on Twitter.



What is the Starling business account?

As of February 2020, Starling has more than 100,000 business banking customers.

A recent upgrade means that business customers can now manage their Starling accounts on a personal computer as well as a smartphone, enabling them to view and export statements to CSV or PDF and save them straight to their desktop.

Other key features of the business account include:

  • no monthly account fees
  • fee-free bank transfers and non-Sterling purchases
  • integration with accounting software Integrate Xero and FreeAgent
  • Post Office deposits from £3 and withdrawals for £0.50

Find out more: business bank accounts - compare fees and benefits



Is my money safe with Starling Bank?


Instant notifications make it easier to notice fraudulent transactions and you can lock your card instantly within the app if it's missing. 

Android users can switch location-based protection on (to prevent fraudulent payments where the location of the card and the app don't match). 

Starling has also gone a step further than its rival Monzo, by allowing users to toggle on and off in-store contactless or chip and Pin payments, ATM withdrawals, online payments and mobile wallet payments. 

If you lose your phone, Starling says it can block the app on that specific device. You can then use a new phone to download the app and log in to your account.


What happens if Starling Bank goes bust?


Starling Bank is regulated by the Financial Conduct Authority (FCA) and authorised by Prudential Regulation Authority (PRA) so up to £85,000 of your money is protected by the Financial Services Compensation Scheme (FSCS).

Monzo Bank review

London-based Monzo Bank got the word out through hackathons and asking tech ‘influencers’ to share its app via word of mouth and Twitter. 

More than two million people are registered for its current account and using its 'hot coral' debit cards and customers rave about the bank. 

Monzo achieved a customer score of 82% in our latest banking satisfaction survey, placing third overall.

However, it won't be selected as a Which? Recommended Provider until it's signed up to the voluntary Authorised Push Payment Scam Code which launched on 28 May 2019.  


What does Monzo Bank offer?


Originally, Monzo offered a contactless prepaid Mastercard linked to its smartphone app but existing users have all been upgraded to a Monzo current account.

As with Starling Bank's app, you get an instant notification every time you use your card as payments clear much faster compared to traditional bank. Monzo customers can even get their salaries a day early - read all about this in our news story

Another major selling point is that there are no fees to pay with your card abroad or make online transactions in a foreign currency.

However, from 31 October 2020, Monzo will charge some customers 3% on cash withdrawals over £250 every 30 days in both the UK and European Economic Area (EEA). And, if you lose or damage your card, you'll pay £5 for card replacements. 

For customers who 'rely' on Monzo (using it to pay bills and receive income) there is no fee for cash withdrawals in the UK and EEA. Outside of the EEA, all standard account holders pay 3% over £200 every 30 days. 

The Monzo Plus packaged account costs £5 per month for various extras including an increased fee-free cash withdrawal limit outside of the EEA (free uo to £400 per 30 days), 1% interest on credit balances up to £2,000, and virtual cards to use online. 

Monzo's first attempt at a packaged account was scrapped after only four months. 

To fund your account, you can have your salary paid in, make a bank transfer, or use Apple and Google Pay.

You an also apply for a pre-arranged overdraft or Monzo personal loan.

Joint accounts are available and Monzo announced on its blog that it is looking to launch business accounts in the future.  

What is the Monzo Bank Marketplace?


Like Starling, Monzo wants to collaborate with other tech firms to offer additional services through its app. 

You can already switch energy providers and in March 2019, it introduced new range of savings accounts partners such as Charter Savings Bank and Shawbrook Bank. Other goals for the Marketplace include cashback, peer-to-peer investments, and mortgages.

Monzo has also integrated with these financial apps: 

  • Emma - a money-management app that helps you avoid overdraft fees, find and cancel subscriptions, and save money.
  • Moneybox - an investment app that rounds up your purchases to the nearest £1 and invests that spare change into one of three tracker funds in a stocks and shares Isa, cash or stocks & shares lifetime Isa or Junior Isa. 

We explain what you need to know about sharing your current account data in our open banking guide.


How do I open a Monzo Bank current account?


Once you've downloaded the Monzo app – from your phone's official App store - setting up the account should only take a few minutes.

You'll be asked for a copy of photo ID (passport or driving licence) and a five second video of yourself to verify your identity.

Monzo does ask for a UK address – to send your debit card – but you can use your work address or a friend’s address if you wish. 


Is my money safe with Monzo Bank?


Instant notifications help you respond to unauthorised payments quickly, and you can temporarily freeze your card via the app (if you've lost it) to prevent anyone else from using it. 

As with other banks, Monzo must refund unauthorised transactions if you’ve been the victim of a genuine fraud, as long as you haven't been careless. 

Turning the location-based security feature on (iPhone only) adds another layer of security. For instance, if your phone is at home and someone tries to pay using your account abroad, the payment should be blocked. 

By default, magstripe ATM withdrawals are disabled to prevent ‘skimming’ (details can be copied from the black stripe on the back of your card using devices attached to legitimate machines), though it can be temporarily enabled. 

Almost all UK cash machines use chip and Pin to validate your identity, but in other countries they use the magnetic stripe to authorise withdrawals.

For lost or stolen phones, Monzo has told Which? it's planning to create an online portal for emergency payments and transfers. 

In the meantime, we would recommend that you maintain an alternative current account so that you can still access money if something goes wrong with your phone, the Monzo app, or your Monzo card. 


What happens if Monzo Bank goes bust?


Monzo Bank is regulated by the Financial Conduct Authority (FCA) and authorised by Prudential Regulation Authority (PRA) so up to £85,000 of your money is protected by the Financial Services Compensation Scheme (FSCS).

Atom Bank review

The Durham-based online bank is co-founded by the former chairman of Metro Bank and the former CEO of First Direct. 

It's raised almost £400m from investors, backed by Spanish Bank BBVA (with a 39% stake), Woodford Investment Management and Toscafund.

For now, it only offers fixed-rate savings accounts, a digital mortgage broker service and business loans. But Atom told Which? that plans are underway to launch an Instant Access Saver later this year, with a current account offering coming after that.




What does Atom Bank offer?


Atom offers fixed-rate savings accounts, residential mortgages and business loans.

As well as 1, 2, 3 and 5-year fixed-rate accounts,you can take out a savings account with a term or three and six months. 

These accounts regularly appear at the top of the Which? Money Compare savings tables. And you don’t need much to get going as all accounts require a deposit of £50 with a maximum of £100,000 allowed. You can also decide if you want to be paid the interest monthly or annually. 

Atom also offers mortgages through its broker service, which you can access via its app. 

A current account is also on the cards. Once that hits the market, you’ll be able to set up direct debits, use an overdraft and have your salary paid into the account.


How do I open an Atom Bank account?


Once you've downloaded the app, it takes about 5 minutes to set up an account. To start, you’ll need to verify your identity via the app with a selfie and by repeating a simple phrase into your phone’s microphone. You don’t need to supply any paper documents such as a passport or proof or address.

You can talk to Atom via its Live Chat function on the app, on the phone, via email or through Twitter.


Is my money safe with Atom Bank?


Once you’ve paid money into your Atom savings account, you can’t withdraw it until the end of your product term, except in cases of financial hardship, so it's highly unlikely that anyone could make a fraudulent withdrawal.

It's important that Atom protects your identity, though – and it does this by registering the devices you use (so that it recognises your phone or tablet) and using biometric technology (your voice and face) to secure the app. 


What happens if Atom Bank goes bust?


All money stored in an Atom Bank savings account is protected by the Financial Services Compensation Scheme, up to £85,000.

Tandem Bank review

Tandem Bank founder Ricky Knock says they hit 500,000 users after only one year, having gained a banking licence and £80m capital when it took over Harrods Bank in 2017.



What does Tandem Bank offer?


The Tandem app is designed to help you manage your money – by providing spending notifications, utility switching support, and alerts should your bill payments increase.

You can ask it to pull in information from existing current accounts from other banks using secure APIs (more on this in our guide to open banking). 

Another impressive app feature is Autosavings, which will round up transactions on linked cards to the nearest pound, and automatically save the difference (so if you buy a coffee for £1.60, the bank will round it up to £2 on your statement and move 40p into your savings account where it earns 0.5% AER). 

Product-wise, Tandem offers two credit cards - both with no fees on purchases abroad and instant in-app spending alerts – and fixed-rate savings accounts over one, two, or three years (minimum deposit of £1,000). 

Its 'Journey' credit card is designed to help users build up credit history, while the 'Cashback' credit card pays 0.5% cashback on worldwide purchases aimed at people with good credit history. 


How do I open a Tandem Bank account?


For a Tandem savings account, you can apply online. You'll need to supply: a mobile phone number (you'll be sent a six-digit security code); your home address for the last three years; the account details of a UK current account (interest will be paid into this account at maturity); and any foreign tax IDs you might have. 

To supply proof of ID, you can either use the Tandem app to start a chat and upload your documents (make sure you download the Tandem app from the official Apple or Android app store). Alternatively, you can post copies of your documents to them. 

For a credit card, apply in-app. Most credit card applications are processed the next working day, so you should get your card and Pin in three to five working days. In other cases, you'll be asked to upload documents proving your identity which will significantly longer, so you may have to wait up to three weeks from application. 


Is my money safe with Tandem Bank?


All your details are held behind a password, and no sensitive information is needed to connect your accounts to the app, only your personal ID. 

Tandem can never transfer money or make changes to your accounts.

If you lose your phone, you can call them up to lock your account, preventing anyone from accessing the app. 


What happens if Tandem Bank goes bust?


All money stored in an Tandem Bank account is protected by the Financial Services Compensation Scheme, up to £85,000.

How safe are e-money firms?

While the likes of Starling and Monzo have banking licences in the UK, the following fin-tech companies operate under electronic or e-money licences instead.

This means you don't get direct protection under the Financial Services Compensation Scheme although your money must be ring-fenced.

The FCA supervises regulated firms to make sure they comply with the regulation and store the funds correctly. In the event of an insolvency, you would be able to claim your funds from this segregated account. 

While protections are in place, think carefully about how much of your savings you're willing to hold in e-money accounts as many brands use the same providers to issue their cards and process payments. 

For example, in June 2020, German company Wirecard AG filed for insolvency and the FCA ordered its UK arm to halt ‘all regulated activity’ to protect accounts. 

As Wirecard Card Solutions Ltd UK  issues cards for a number of companies - including Curve, Anna Money, Pockit, FairFX and Dozens - this effectively locked millions of prepaid card customers out of their accounts for several days, until the FCA lifted its restrictions. 

On 28 August 2020, Wirecard Card Solutions Ltd announced on its website that it is intending to close its FCA-regulated business and sell it to Railsbank, a UK open banking startup backed by Visa. 

Revolut review

Set up by a Credit Suisse equity analyst and a former Deutsche bank app developer in July 2015, Revolut is aiming to shake up the travel exchange market.

Revolut claims its rates save customers 3% to 5% because it uses the 'Spot Interbank' exchange rate, the wholesale exchange rate. The firm has more than four million users worldwide. 

  • Which? has reported on various scams targeting Revolut users including malicious Google adverts which supply fake customer service phone numbers. Revolut users should only use the in-app chat function.



What does Revolut offer?


You have three options: the Standard, Premium, or Metal accounts - all of which come with prepaid Mastercard that lets you spend abroad in over 150 currencies and exchange money in 29 currencies in-app:

  • Revolut Standard is free and allows cardholders to spend, transfer and exchange up to £5,000/€6,000 in total every month (a 0.5% fee applies after this). ATM withdrawals are free up to £200 a month, then 2%.
  • Revolut Premium costs £6.99 a month and allows for unlimited spending, a more generous £400 cash withdrawal limit, plus worldwide travel insurance and a LoungeKey airport lounge pass. 
  • Revolut Metal cardholders pay £12.99 a month for all of the Premium benefits with a £600 cash withdrawal limit, 0.1% cashback within Europe and 1% outside Europe on all card payments, plus an exclusive steel card. 

The Premium and Metal accounts also come with disposable virtual cards, designed to prevent online fraud. 

As with Monzo and Starling, app features include bill splitting functionality; a spending summary; and real-time notifications of transactions. 

Revolut doesn't accept cheques or cash deposits but you can top it up by bank transfer, debit or credit card, as well as Apple or Google Pay.

But, you can’t set up direct debits or standing orders via Revolut, so this has less functionality that Starling and Monzo Bank, which offer a full current account. 

It’s worth knowing that Revolut applies a minor mark up on its rates at the weekend of 0.5%- 1.5% as the markets are closed.

Additional Revolut products

Revolut has been developing its products and features quickly, largely through partnerships with other firms:

  • Lending Works peer-to-peer loans ranging from £500 up to £25,000 repaid over 12 to 60 months.
  • Simplesurance phone or device cover from 90p per week;
  • Thomas Cook Group pay-per-day medical and dental travel insurance from £1 per day or fixed at £30 for an annual policy; 
  • Hold, exchange and transfer in cryptocurrency via the Bitstamp cryptocurrency exchange (Premium and Metal only for now) with a 1.5% fee.

Future plans include an integrated investment platform that will allow customers to invest large sums or their spare change into stocks and bonds. 


How do I open a Revolut account?


To sign up, you don't need to supply proof of address, go through a credit check or pay a trip to a high street bank branch. But it will cost you £5 to order a card to a UK address (£12 for express delivery). 

The Premium card comes with free express delivery. Once you have the card you can start using it in 30 seconds.

Revolut has a 'chatbot' called Rita to answer commonly asked questions, as well as live-chat on the app and via Twitter. If the chatbot can’t help, you'll be transferred to a Revolut customer service 

The tech firm is planning to expand Rita’s capabilities so you can get useful answers to more specific questions such as ‘How much did I spend on beer last month?’ or ‘How much do I spend on Uber?’. 


Is my money safe with Revolut?


If your card is lost or stolen, you can block the card via in-app support, or over the phone.

Revolut users can opt-in to location-based security to prevent fraudulent transactions e.g. if you and your phone are in Germany and a transaction is attempted in Hong Kong with your card details, it should stop this payment from going through.

You can also enable or disable your physical Revolut card in a single tap if it's lost or stolen. Other features that can be instantly turned on and off in-app include ATM withdrawals, online payments, contactless and magstripe payments. 


What happens is Revolut goes bust?


Your money isn't protected by the Financial Services Compensation Scheme because Revolut operates under an e-money licence in the UK (despite having Lithuanian banking licence). It is not a regulated bank in the UK. 

However, your money is held in ring-fenced client accounts with Barclays or Lloyds which means your money can’t be lent out by Revolut. 

In the event of an insolvency, you would be able to claim your funds from this segregated account. 

Monese review

Monese was founded by Norris Koppel after he realised he couldn’t get a bank account as an Estonian immigrant.

The bank is on a mission to remove as many hurdles as possible from setting up a bank account in the UK and gears itself towards foreign nationals, expats, freelancers and those who would otherwise have to apply for a basic bank account

It provides mobile-only UK and European current accounts, small business accounts, and is available in 31 countries in Europe. 

In May 2019, it reached one million customers across Europe and announced that more than 3,000 people are joining Monese everyday.



What does Monese offer?


Monese isn’t technically a bank so it can’t make loans, invest money or provide interest. But, it does let you open a bank account without a UK address, providing you with a sort code and account number so that you can set-up direct debits and make or receive payments.

Different benefits and fees apply depending on whether you choose the 'Starter', 'Classic' or 'Plus' account (terms apply from 1 July 2019):

Monese Starter – no monthly fee

The account is free to open and run but other fees apply. 

When adding money to your account, incoming bank transfers are free and you get an allowance of £200/€200 per 30 days for ATM withdrawals and loading your account with cash via the Post Office, PayPoint, cashback in stores and Sofort.

If you exceed this limit, you pay 2% per transaction. 

Spending on your card in a foreign currency is free up to £2,000/ €2,000 per 30 days then 2% per transaction. 

When you make outgoing international payments via the app, your money is converted at the Mastercard wholesale exchange rate plus currency exchange fees of at least 2% of the transaction value. 

Monese Classic – £4.95 monthly fee

For a monthly fee of £4.95, you benefit from an increased allowance of £800/€800 per 30 days for top ups via the Post Office, Paypoint, cashback in stores and Sofort (the 2% per transaction fee still applies after this). 

Spending on your card in a foreign currency is free up to £8,000/ €8,000 per 30 days then 2% per transaction. 

Monese also reduces currency exchange fees to 0.5% (minimum fee £2/€2) for international bank transfers via the app. 

Monese Premium – £14.95 monthly fee

The most expensive account, costing £14.95, offers unlimited free transfers, top-ups and ATM withdrawals. 


How do I open a Monese account?


It takes around five minutes to set up the mobile app via iOS or Android, though Windows phones aren’t supported. You take a video ‘selfie’, say a short sentence, take a photo of your passport and fill in a few basic details.

To set up an account, you don’t need a fixed income, proof of address or a good credit history

You can chat to Monese via its Estonia-based customer support line (this is routed through a Manchester number so you don’t pay anything), on the app itself, via email and its Twitter page. If you call up, there's usually a waiting time of around four to five minutes.


Is my money safe with Monese?


Real-time notifications are sent to your smartphone app when you spend. You can block your card in-app if you notice an unusual transaction or lose your card. 

What happens if Monese goes bust?


The Monese prepaid debit card is issued by PrePay Technologies Limited which has an e-money licence not a UK banking licence so there is no FSCS-protection

However, funds are ring-fenced in a separate account which means your money can’t be lent out by Monese. 

If Monese or PrePay Technologies went bust, you would be able to claim your funds from this segregated account and your money is protected against claims made by creditors.

Nimbl review

Available for eight to 18-year-olds, Nimbl allows parents to track their child’s spending, while incentivising small savings each month, all in the name of a healthy financial future.

Nimbl told us it has 69,246 users (parents and children). 



What does Nimbl offer?


Nimbl’s prepaid Mastercard, linked to an app, allows parents to track their children’s spending and set spending limits through its app. It claims that using its app will promote financial responsibility among children. 

The card costs £28 a year. Cash withdrawals are now free at ATMs in the UK. To replace a lost or stolen card it costs £5. 

A micro-savings feature lets children automatically transfer a set amount of money – 50p, £1 etc – each time the card is used.

Both children and parents can view statements to review spending.


How do I open a Nimbl account?


To sign up and receive a contactless prepaid card, you fill in some basic contact details online and your child’s name, which takes up to 10 working days to arrive. 

You can call Nimbl from 8am-8pm weekly and Saturdays, or email/Tweet them with any issues.


Is my money safe with Nimbl?


Parents set spending limits and choose whether the card can be used in store, online or for withdrawing cash. 

Real-time notifications are sent to the parent's phone to see how much the child is spending, where they’re spending and where they are. If the card goes missing, it can be locked remotely through the app. 

Payments to registered age-inappropriate bookmakers, casinos and off-licences are blocked, although Nimbl can't prevent payments at permitted retailers such as supermarkets. 


What happens if Nimbl goes bust?


As with the other non-banks in our list, Nimbl can't lend your money out and isn't covered by the Financial Services Compensation Scheme. 

Instead, the card – issued by PrePay Technologies Ltd – and any money stored in your account is backed by e-money regulations. 

If Nimbl or PrePay Technologies went bust, you would be able to claim your funds from this segregated account and your money is protected against claims made by creditors.