There are different timings for payments to different accounts.
If you are transferring money between your own accounts, it's immediate, except for between the following types of accounts:
Please allow two Business Days for the credit card payment to be processed.
Please note - charges and interest will be payable if you miss your card payment due date in accordance with your terms and conditions. Interest will be charged on all transactions shown on your statement, calculated from the date each transaction was added to your account until full payment is made and credited to your account. This will happen even if you had paid your previous statement balance in full and on time.
If you transfer funds to a different bank, or to a different recipient, these are processed via the Faster Payments service and should normally reach the payee's account immediately.