Guidance

Corporation Tax technical specifications for CT600 RIM artefacts

CT600 V3 (2026) and V2 (2009) RIM artefacts for Corporation Tax software developers.

• From: HM Revenue & Customs
• Published: 13 August 2014
• Last updated: 25 September 2026
  Show all updates

  1. 25 September 2026

     CT600 V3 (2026) Artefacts V1.995 has been added.

  2. 7 April 2026

     CT600 V3 (2025) Artefacts V1.993 has been removed. CT600 V3 (2026) Artefacts V1.994 is now live.

  3. 23 December 2025

     The CT600 V3 (2026) Artefacts V1.994 has been updated to show it supports Third Party Validation Service (TPVS) and is awaiting implementation into live. CT600 V3 (2025) Artefacts V1.993 status has been updated to 'Currently in live'.

  4. 2 December 2025

     CT600 V3 (2026) Artefacts V1.994, and CT600 V3 (2025) Artefacts V1.993 have changed status.

  5. 10 October 2025

     CT600 V3 (2026) Artefacts V1.994 has been added.

  6. 6 April 2025

     The CT600 V3 (2025) Artefacts V1.993 status has been updated to show it supports Local Test Service (LTS) and Third Party Validation Service (TPVS) and is now live. CT600 V3 (2024) Artefacts V1.992 status has been removed as it is no longer available.

  7. 24 February 2025

     The CT600 V3 (2025) Artefacts V1.993 status has been updated to show it supports Local Test Service (LTS) and Third Party Validation Service (TPVS) and is awaiting implementation into live. CT600 V3 (2024) Artefacts V1.992 status has been updated as it is now only in live.

  8. 27 January 2025

     The CT600 V3 (2025) Artefacts V1.993 status has been updated to awaiting implementation into Third Party Validation Service (TPVS) and live. CT600 V3 (2024) Artefacts V1.992 status has been updated as it is now in Third Party Validation Service (TPVS) and live.

  9. 6 December 2024

     CT600 V3 (2025) Artefacts V1.993 has been added.

  10. 6 April 2024

      CT600 V3 (2023) Artefacts V1.991 has been removed. CT600 V3 (2024) Artefacts V1.992 is now live.

  11. 2 February 2024

      CT600 V3 (2024) Artefacts V1.992 status updated from 'Awaiting implementation into LTS, TPVS and live' to 'Currently LTS, TPVS and awaiting implementation into live'. CT600 V3 (2023) Artefacts V1.991 updated from 'Currently LTS, TPVS and live' to 'Currently live'.

  12. 9 October 2023

      CT600 V3 (2024) Artefacts V1.992 has been added.

  13. 6 April 2023

      CT600 V3 (2022) Artefacts V1.99 has been removed. CT600 V3 (2023) Artefacts V1.991 is now live.

  14. 20 March 2023

      CT600 V3 (2022) Artefacts V1.99 status updated to currently live. CT600 V3 (2023) Artefacts V1.991 status updated to currently Local Test Service (LTS), Third Party Validation Service (TPVS) and awaiting implementation into live.

  15. 21 December 2022

      CT600 V3 (2023) Artefacts V1.991 has been added.

  16. 20 September 2022

      CT600 V3 (2022) Artefacts V1.97 has been removed. CT600 V3 (2022) Artefacts V1.99 has been changed to 'Currently Local Test Service (LTS), Third Party Validation Service (TPVS) and live'.

  17. 5 September 2022

      CT600 V3 (2022) Artefacts V1.99 has been changed to 'Currently in Local Test Service (LTS), Third Party Validation Service (TPVS) and is awaiting implementation into live'. CT600 V3 (2022) Artefacts V1.97 has been changed to 'Currently in live'.

  18. 7 July 2022

      We have published CT600 V3 (2022) Artefacts V1.99 — V1.98 was not released externally. CT600 V3 (2022) V1.99 has been changed to awaiting implementation into Local Test Service (LTS), Third Party Validation Service (TPVS) and live.

  19. 7 April 2022

      CT600 V3 (2021) V1.96 has been removed. CT600 V3 (2022) Artefacts V1.97 has been changed from 'currently in LTS, TPVS and awaiting implementation in live' to 'currently in LTS, TPVS and live'.

  20. 3 March 2022

      CT600 V3 (2022) Artefacts V1.97 has been changed from Awaiting implementation into LTS, TPVS and live to Currently in LTS, TPVS and awaiting implementation in live.

  21. 24 September 2021

      CT600 V3 (2022) Artefacts V1.97 has been added.

  22. 22 February 2021

      CT600 V3 (2021) V1.96 has been added.

  23. 22 September 2020

      CT600 V3 (2021) Artefacts V1.95 added.

  24. 14 July 2020

      CT600 V3 (2020) Artefacts V1.94 has been changed from 'Currently live. Awaiting implementation into LTS, TPVS and live.' to 'Currently LTS, TPVS and live.', and CT600 V3 (2020) Artefacts V1.93 has been removed.

  25. 29 May 2020

      CT 600 V3 (2020) Artefacts V1.94 added.

  26. 6 May 2020

      CT600 V3 (2019) Artefacts V1.92 removed.

  27. 8 October 2019

      V3 (2020) Artefacts V1.93 has been added.

  28. 16 April 2019

      The CT600 V3 (2018) Artefacts V1.9 has been updated to CT600 V3 (2019) Artefacts V1.92.

  29. 13 April 2018

      V3 (2017) Artefacts V1.8 has been removed.

  30. 31 January 2018

      The V3 (2015) Artefacts V1.7 has been superseded by V1.8 and CT600 V3 (2018) Artefacts V1.9 has been added.

  31. 19 October 2017

      CT600 V3 (2015) Artefacts V1.8 has been added.

  32. 21 December 2016

      The CT600 V3 (2015) Artefacts V1.4 has been updated to version V1.7.

  33. 22 July 2015

      The CT600 V2 (2009) Artefacts V3.98 has been updated to version V3.99 and the CT600 V3 (2015) Artefacts V1.3 has been updated to version V1.4.

  34. 9 February 2015

      Updated ZIP versions.

  35. 13 August 2014

      First published.

Documents

CT600 V3 (2026) Artefacts V1.995

ZIP, 6.75 MB

This file may not be suitable for users of assistive technology.

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CT600 V3 (2026) Artefacts V1.994

ZIP, 6.7 MB

This file may not be suitable for users of assistive technology.

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If you use assistive technology (such as a screen reader) and need a version of this document in a more accessible format, please email different.format@hmrc.gov.uk. Please tell us what format you need. It will help us if you say what assistive technology you use.

CT600 V2 (2009) Artefacts V3.99

ZIP, 2.3 MB

This file may not be suitable for users of assistive technology.

Request an accessible format

If you use assistive technology (such as a screen reader) and need a version of this document in a more accessible format, please email different.format@hmrc.gov.uk. Please tell us what format you need. It will help us if you say what assistive technology you use.

Details

CT600 V3 (2027) Artefacts V1.995

Version date 25 September 2026.
Awaiting implementation into Local Test Service (LTS), Third Party Validation Service (TPVS) and live.

CT600 V3 (2026) Artefacts V1.994

Version date 10 October 2025.
Currently Local Test Service (LTS), Third Party Validation Service (TPVS) and live.

CT600 V2 (2009) Artefacts V3.99

Version date 19 June 2015.
Currently Local Test Service (LTS), Third Party Validation Service (TPVS) and live.