Guidance

Supplementary pages CT600K: Restitution Tax

How to complete supplementary pages CT600K and what information you need to include.

When to complete

Complete these supplementary pages if the company:

Restitution interest means profits in relation to which conditions A to C are met.

Condition A

That the profits are interest paid or payable by HMRC in respect of a claim by the company for restitution with regard to either of the following matters (or alleged matters):

  • the payment of an amount to HMRC under a mistake of law relating to a taxation matter
  • the unlawful collection by HMRC of an amount in respect of taxation

Condition B

That:

  • a court has made a final determination that HMRC is liable to pay the interest
  • HMRC and the company, have in final settlement of the claim, entered into an agreement under which the company is entitled to be paid, or is to retain, the interest

Condition C

That the interest determined to be due, or agreed upon, is not limited to simple interest at a statutory rate.

Read section S357YC of the Corporation Tax Act 2010 for more information about the meaning of restitution interest.

You should note that:

  • Corporation Tax is charged on restitution interest at the restitution payments rate, this is currently 45%
  • in the calculation of tax liability on the restitution interest, Corporation Tax reliefs or reductions for any amounts of Income Tax or Corporation Tax, or any other amounts, are excluded from the calculation (read section S357YL of the Corporation Tax Act 2010 for more information)
  • an amount deducted from an interest payment is treated for all purposes as paid by the company on account of the company’s liability to Corporation Tax chargeable on the restitution interest (read section S357YP of the Corporation Tax Act 2010 for more information)

Company information

K1 Company name

Enter the company name.

K2 Tax reference

Enter the company’s 10-digit Unique Taxpayer Reference.

Period covered by this supplementary page (cannot exceed 12 months)

K3

Enter the start date using the format DD MM YYYY.

K4

Enter the end date of the accounting period using the format DD MM YYYY.

Details of tax calculation

K5 Self-assessment of tax payable before restitution tax

Enter the figure from box 525 of your CT600 form.

K10 Restitution interest

Enter the amount of restitution interest arising in the accounting period.

K15 Columns A to D

Enter the amount of interest chargeable at each rate of tax, and the amount of tax for each financial year.

K20 Total restitution tax

Enter the sum of D1 and D2.

K25 Tax already withheld

Enter the amount of tax withheld from the payment that relates to this accounting period (read section 357YO of the Corporation Tax Act 2010). The amount in this box cannot exceed the amount in box K20.

K30 Self-assessment of tax payable after restitution tax

Enter the sum of box K5 and K20 minus the amount in box K25.

K35 Restitution tax now payable

Enter the figure in box K20 minus the figure in box K25.

Enter this figure in box 527 of your CT600 form.

Updates to this page

Published 30 September 2022
Last updated 2 January 2024 + show all updates
  1. Added translation

  2. First published.

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