This part of GOV.UK is being rebuilt – find out what beta means

HMRC internal manual

Self Assessment Claims Manual

Provisional Claims and Provisional Figures in Claims: Penalties

If the customer fails to submit the return or the claim by the statutory filing date or by the date specified in the letter that accompanied the return/claim sent back as being unsatisfactory, a penalty may be imposed under FA09/Sch55.

Should we establish that there was no good reason for the inclusion of provisional figures or that the estimate use was not calculated on a reasonable basis, a penalty may be imposed under FA07/Sch24.

Any unreasonable delay in providing the final figures, after they have been established, may lead to the imposition of a penalty under FA07/Sch24.