Current Account Switch Service: What CASS Actually Does

Detailed comparison framework

CASS is the infrastructure behind most full UK current-account switches. It standardises the move between participating providers, but it does not decide whether you qualify for a bank's promotional bonus or whether the destination account itself is a good fit.

A full CASS switch is designed to complete in seven working days

The Current Account Switch Service lets customers choose an agreed switch date and moves the old current account to the new provider on a seven-working-day timetable. A full switch closes the old account rather than leaving two current accounts running in parallel.

This timetable is separate from account opening. Identity checks, credit assessment or overdraft approval can take place before the formal switch begins. When planning around salary or bills, distinguish the date the new account opens from the date the seven-working-day switch process starts.

For this cass section, the control point is 'A full CASS switch is designed to complete in seven working days'. Use CASS as the authoritative process layer: account opening can happen before the seven-working-day switch, while provider offers and overdraft decisions remain separate commercial rules. Record the assumption used for section 1, attach the current source or saved offer terms, and test one failure case before treating the apparent value as reliable. This keeps the explanation usable when a provider changes a bonus, deadline, fee, benefit or eligibility rule without changing the broader switching process.

Regular incoming and outgoing payments are moved or redirected

CASS transfers eligible Direct Debits and standing orders and redirects incoming payments sent to the old account details. The service also tells payment originators about the new account information so future payments can be updated.

Recurring debit-card subscriptions are different because they use card credentials rather than a bank-account mandate. They can require manual updating after the old debit card is replaced. Build a separate card-subscription checklist rather than assuming every automatic payment moves through CASS.

For this cass section, the control point is 'Regular incoming and outgoing payments are moved or redirected'. Use CASS as the authoritative process layer: account opening can happen before the seven-working-day switch, while provider offers and overdraft decisions remain separate commercial rules. Record the assumption used for section 2, attach the current source or saved offer terms, and test one failure case before treating the apparent value as reliable. This keeps the explanation usable when a provider changes a bonus, deadline, fee, benefit or eligibility rule without changing the broader switching process.

The old account closes and the balance moves on the switch date

A full CASS switch includes closure of the old current account and transfer of its balance to the destination account. That closure is why full switching can qualify for promotions that do not accept partial or manual moves.

Before the date arrives, review pending card transactions, cheques, cash access and any overdraft use. CASS moves the account relationship, but a pending merchant transaction or an overdraft application can have its own timing. Keep enough liquidity available to absorb short operational mismatches.

For this cass section, the control point is 'The old account closes and the balance moves on the switch date'. Use CASS as the authoritative process layer: account opening can happen before the seven-working-day switch, while provider offers and overdraft decisions remain separate commercial rules. Record the assumption used for section 3, attach the current source or saved offer terms, and test one failure case before treating the apparent value as reliable. This keeps the explanation usable when a provider changes a bonus, deadline, fee, benefit or eligibility rule without changing the broader switching process.

The Current Account Switch Guarantee covers switch-caused problems

The guarantee places responsibility for the switching process with the new bank or building society. If something goes wrong because of the switch, the destination provider is responsible for correcting the problem and refunding qualifying charges or interest caused by the failure.

Keep evidence of the switch date and any financial consequence. A missed payment caused by the switch is different from an employer failing to run payroll or a merchant collecting the wrong Direct Debit amount. Those other failures have their own resolution routes, so identify the cause before escalating.

For this cass section, the control point is 'The Current Account Switch Guarantee covers switch-caused problems'. Use CASS as the authoritative process layer: account opening can happen before the seven-working-day switch, while provider offers and overdraft decisions remain separate commercial rules. Record the assumption used for section 4, attach the current source or saved offer terms, and test one failure case before treating the apparent value as reliable. This keeps the explanation usable when a provider changes a bonus, deadline, fee, benefit or eligibility rule without changing the broader switching process.

CASS does not guarantee a switching bonus or an overdraft transfer

Promotional eligibility belongs to the provider's offer terms, not to CASS. You can complete a technically successful seven-working-day switch and still miss a cash incentive because a Direct Debit, pay-in, card-payment or historic-customer condition was not satisfied.

An overdraft also does not simply move as a debt facility to the new bank. The destination provider assesses any new overdraft separately. If you depend on arranged borrowing, confirm the new facility before scheduling closure of the old account. Use CASS for the plumbing and provider terms for the commercial decision.

For this cass section, the control point is 'CASS does not guarantee a switching bonus or an overdraft transfer'. Use CASS as the authoritative process layer: account opening can happen before the seven-working-day switch, while provider offers and overdraft decisions remain separate commercial rules. Record the assumption used for section 5, attach the current source or saved offer terms, and test one failure case before treating the apparent value as reliable. This keeps the explanation usable when a provider changes a bonus, deadline, fee, benefit or eligibility rule without changing the broader switching process.

Sources and related guides

CASS mechanics were checked on 30 September 2026 against the scheme operator rather than provider marketing. Future reviews should verify the seven-working-day timetable, eligible payment migration, incoming-payment redirection, account closure and guarantee wording directly with CASS. Provider cash incentives, destination-account fees and overdraft decisions should remain outside the scheme explanation because they can change independently and are not guaranteed by CASS.

For this cass section, the control point is 'Sources and related guides'. Use CASS as the authoritative process layer: account opening can happen before the seven-working-day switch, while provider offers and overdraft decisions remain separate commercial rules. Record the assumption used for section 6, attach the current source or saved offer terms, and test one failure case before treating the apparent value as reliable. This keeps the explanation usable when a provider changes a bonus, deadline, fee, benefit or eligibility rule without changing the broader switching process.

• BankOfferScout - Current Account Switch Service hub
• Current Account Switch Service - switching process
• Current Account Switch Service - common questions
• Current Account Switch Service - about the service

Related Guides:

• How the Current Account Switch Service Works
• How Long a Bank Switch Takes
• What Happens to Salary Payments When You Switch