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HMRC internal manual

Stamp Taxes on Shares Manual

Compliance: Stamp Duty interest: Part payment

A document cannot be stamped until the stamp duty, penalty and interest are paid in full.

If the stamp duty due is paid in full within 30 days of the date of execution, no interest is payable. If part of the duty is paid within the 30 day period but the balance is not paid until later, interest will only be due on the balance remaining unpaid after the end of the 30 days.

If the first payment of duty falls after the 30 day period but is only part of the payment due, interest will be due on the total amount of duty up to the date of the first payment then on the balance from then until the next payment and so on until the duty is paid in full.

The stamping of a document is sometimes delayed because the consideration is not yet ascertained (STSM017020). In these “wait and see” cases, a payment may be made on account of the stamp duty due. If such a payment on account is less than the final amount due, it is treated for interest purposes in the same way as a part payment (above).