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HMRC internal manual

COTAX Manual

Returns / notices: notices and returns: form CT600

Form CT600
Paper returns

Form CT600

Returns for accounting periods ending after 31 March 2010 must be submitted electronically through the Corporation Tax Online Service. There are some exceptions.

  • Companies run entirely by individuals who are practising members of a religious society or order whose beliefs are incompatible with the use of electronic communications are not required to file online. COM130065 has more information.

You must download and print a form CT600 from the HMRC website and post it to these companies.

  • Insolvent companies within a formal administration or winding up procedure are excluded from the legal requirement to file online. However, solvent companies being wound up under a members’ voluntary liquidation are not excluded from online filing. See COM130050 for further information.

The return form is a CT600 and may need to be accompanied by supplementary pages which, when completed, form part of the company tax return.

Validation rules make sure that all mandatory parts of the electronic CT600 and any supplementary pages are completed. The rules also make sure that there are no arithmetical errors.

Supplementary pages must be included where the following circumstances apply.

CT600A (Close company loans or arrangements to confer benefits on participators).

Loans have been made to participators by close companies.

CT600B (Controlled foreign companies and foreign permanent establishment exemptions).

A UK company has a 25% interest in a foreign company that is controlled from the UK or is subject to the Bank Levy.

CT600C (Group and consortium relief).

Claims or surrenders are made under the group and consortium relief provisions or for eligible unrelieved foreign tax (EUFT).

CT600D (Insurance).

Claims are made under Schedule 19AB ICTA 1988 by insurance companies (including corporate members of Lloyd’s) or friendly societies.

CT600E (Charities and Community Amateur Sports Clubs (CASCs)).

Claims are made to exemption by charities and Community Amateur Sports Clubs.

CT600F (Tonnage Tax).

A company operates ships and is party to a Tonnage Tax election.

CT600G (Corporate Venturing Scheme).

Claims are made under the Corporate Venturing Scheme. Claims can only apply to the period from 1 April 2000 to 31 March 2010 and is not available with the CT600 v3.

CT600H (Cross-border Royalties).

Claims are made for relief for cross border royalties.

CT600I (Supplementary charge in respect of ring fenced trades).

A supplementary charge on ring fence trades applies.

CT600J (Disclosure of tax avoidance schemes).

A company uses or intends to use tax avoidance schemes.

CT600K (Restitution tax)

A company is:

  • chargeable to corporation tax on restitution interest under Part 8C of CTA 2010 and
  • has restitution interest that is not exempt from the restitution tax charge.

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The person making the return for the company must make a declaration to the effect that the return is, to the best of his or her knowledge, complete and correct. This does not mean that it has to have a signature.

A return delivered through the Corporation Tax Online Service includes the name of a person authorised by the company to access and use the Corporation Tax Online Service to deliver its return.

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Paper returns

A paper version of a return is only required for cases that are exceptions to mandatory online filing, such as where there is religious objection or severe IT problems that lead to HMRC giving a dispensation for submission of a paper return.

The CT600 version 3 does not have a signature box. As long as the declaration is completed with the name and status of the person authorising the return, it is acceptable.

You should accept the return or amended paper return as long as you have no reason to doubt the authority of the person whose name is on the declaration. You should accept the name of any company official, employee or agent, including a tax advisor or an accountant, on this basis. You may also accept returns where the declaration is made in the name of a firm of accountants.

When a company is in liquidation, the liquidator must make the declaration. You may accept returns where the declaration has been completed on behalf of the liquidator, for example, by an insolvency manager.

The treasurer or acting treasurer should normally make the declaration for an unincorporated association.

Refer the case at once to Process Design & Excellence’s Tax Administration, Litigation and Advice (TALA) if the declaration on a return is either in the name of a firm of accountants, or on behalf of a liquidator and the company later contends that the return is not valid because it was not a valid declaration.

You can find information on making the referral by going to the Central Tax and Strategy Group website, selecting the Central Policy link, the What We Do link then Tax Administration Advice.

See COM130011 for a list of forms relevant to this subject.