Switching your main bank account in the UK is easier and safer than most people expect, because it runs on a single official system called the Current Account Switch Service (CASS). It is free, it is guaranteed, and it does almost all of the moving parts for you. This guide explains how it works, what to check first, and how the cash switch bonuses fit in, without the jargon.
What the Current Account Switch Service is
CASS is owned and operated by Pay.UK, the organisation behind the UK's main interbank payment systems. Nearly every major bank and building society takes part. The service is free to use, and it is designed so that switching is, in its own words, simple, secure and guaranteed.
The key promise is the Current Account Switch Guarantee. If anything goes wrong during the switch, your new bank refunds any interest or charges you pick up on your old or new account as a direct result of the mistake. The guarantee is provided by the bank or building society you switch to.
The 7 working day guarantee
A full switch completes in 7 working days. You pick the switch date yourself when you apply, and it cannot land on a weekend or a bank holiday. You keep using your old account right up to the agreed date, then everything moves across.
What moves automatically
- Your balance is transferred to the new account.
- Your Direct Debits and standing orders are set up on the new account.
- Incoming payments, such as your salary or benefits, are pointed at the new account.
- Your old account is closed by your old bank on the switch date. You do not need to do it yourself.
- If anyone still sends money to, or tries to take a payment from, your old account, the payment is automatically redirected to your new account and the sender is told your new details.
The switch, step by step
- Choose the account you want and check you are eligible (see conditions below).
- Apply to open the new account and ask for a full switch using CASS, picking your switch date.
- Carry on using your old account as normal until that date.
- On the switch date, your balance, payments and Direct Debits move over and your old account closes.
- Within 7 working days the switch is complete and your new account is running.
Full switch vs partial switch
A full switch closes your old account and moves everything, and it is the only version covered by the Current Account Switch Guarantee. You can instead do a partial switch and keep your old account open, but you will not be able to use CASS to do it and you will not be covered by the guarantee. If you want the protection and the redirection service, choose the full switch.
How the switch bonuses work
Banks compete for main-account customers, so they pay cash bonuses to people who switch in. The amounts and deadlines rotate constantly, which is why we treat every figure as indicative and link you to each bank's own page rather than quoting a number that may be stale. You can see the current line-up on our UK bank switching bonuses list.
Most cash-bonus offers share a similar shape. Expect to be asked to:
- Complete a full switch through CASS, not a partial one.
- Move a set number of active Direct Debits, often two or more.
- Pay in a minimum amount within a set window, sometimes with a few debit card payments or app logins on top.
Three things to check before you switch
1. Is your money still protected?
Money in a UK current account with an authorised bank or building society is protected by the Financial Services Compensation Scheme (FSCS). The FSCS protects up to £120,000 per eligible person, per banking institution (a limit that rose from £85,000 on 1 December 2025). The limit applies per banking licence, so if two brands share a licence, your balances across both are added together under one limit. Worth knowing if you spread large balances around.
2. Will it affect your credit?
Opening a new account may involve a credit check, which can affect your credit rating. On the other hand, the switch service notes that closing your old account through a proper switch can make a positive contribution to your score. If you are actively building credit, our credit builder guide explains how to do that safely, and the golden rule is always to pay any card in full.
3. Do the perks actually suit you?
Some accounts carry a monthly fee, a minimum monthly pay-in, or perks like cashback, interest or travel cover that only pay off if you use them. A one-off bonus is nice, but the account you keep matters more. Many people pair a switch with a fee-free app account for day-to-day spending; see our fintech and challenger banks section for those.
The short version
Use a full switch through CASS, pick your date, and let the service move your balance, Direct Debits and incoming payments within 7 working days. Keep enough in the old account to cover pending payments until the switch date, meet the bonus conditions exactly, and check the exclusions first. Then verify the current offer on the bank's own page before you apply.
Primary sources, checked 7 August 2026
- Current Account Switch Service, the switching process and 7 working day timing: currentaccountswitch.co.uk/the-switching-process-personal
- Common questions, the guarantee, account closure, credit check and partial switch: currentaccountswitch.co.uk/common-questions-personal
- About the service and Pay.UK as operator: currentaccountswitch.co.uk/about-the-service
- FSCS deposit protection limit of £120,000 per banking institution, per licence: fscs.org.uk/what-we-cover/banks-building-societies