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HMRC internal manual

Compliance Handbook

Penalties for failure to pay on time: rules for specific taxes: Stamp Duty Reserve Tax (SDRT): failure to pay all or part of amounts due - initial penalty

A person incurs an initial penalty when they do not pay the SDRT 30 days after the accountable date for payment. The 31st day after the accountable date for payment is known as the penalty date.

The amount of the initial penalty is 5% of the amount unpaid at the penalty date.