Guidance

Payroll technical specifications: National Insurance

National Insurance guidance for software developers working with payroll software.

• From: HM Revenue & Customs
• Published: 1 January 2014
• Last updated: 24 June 2026
  Show all updates

  1. 24 June 2026

     National Insurance guidance for software developers (2026 to 2027) — effective from 6 April 2026 has been updated.

  2. 29 January 2026

     National Insurance guidance for software developers (2026 to 2027) has been added. National Insurance guidance for software developers (2020 to 2021) has been removed.

  3. 8 January 2025

     National Insurance guidance for software developers (2025 to 2026) has been added. Guidance for 2019 to 2020 has been removed.

  4. 11 March 2024

     National Insurance guidance for software developers (2024 to 2025) has been updated.

  5. 31 January 2024

     National Insurance guidance for software developers (2024 to 2025) has been added. Guidance for 2018 to 2019 has been removed.

  6. 13 December 2023

     National Insurance guidance for software developers effective from 6 January 2024 has been added.

  7. 30 January 2023

     National Insurance guidance for software developers effective from 6 April 2023 has been added. Guidance for 2017 to 2018 has been removed.

  8. 30 September 2022

     National Insurance guidance effective from 6 November 2022 has been added. Guidance for 2014 to 2015, 2015 to 2016 and 2016 to 2017 has been removed.

  9. 28 April 2022

     National Insurance guidance has been added to be used from 6 July 2022 until the end of the tax year 2022 to 2023.

  10. 17 January 2022

      The 2022 to 2023 National Insurance guidance for software developers has been added.

  11. 10 September 2021

      The 2021 to 2022 National Insurance guidance for software developers has been added.

  12. 4 August 2020

      The 2020 to 2021 National Insurance guidance for software developers has been added.

  13. 29 January 2019

      The 2019 to 2020 National Insurance guidance for software developers has been added.

  14. 17 January 2018

      The December 2017 version of the NI Guidance for Software Developers specification has been replaced with the January 2018 version.

  15. 3 January 2018

      The 2018 to 2019 National Insurance guidance for software developers has been added.

  16. 23 December 2016

      NI guidance for software developers (2017 to 2018) has been published

  17. 6 January 2016

      The National Insurance guidance for software developers (2016 to 2017) attachment has been added to the page.

  18. 28 January 2015

      Example 4 (pages 38 to 41) revised January 2015.

  19. 1 January 2014

      First published.

Documents

National Insurance guidance for software developers (2026 to 2027) — effective from 6 April 2026

ODT, 117 KB

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National Insurance guidance for software developers (2025 to 2026) — effective from 6 April 2025

ODT, 142 KB

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National Insurance guidance for software developers (2024 to 2025) — effective from 6 April 2024

ODT, 130 KB

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National Insurance guidance for software developers (2023 to 2024) — effective from 6 January 2024

ODT, 142 KB

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National Insurance guidance for software developers (2023 to 2024) — effective from 6 April 2023 to 5 January 2024

ODT, 127 KB

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National Insurance guidance for software developers (2022 to 2023) — effective from 6 November 2022

ODT, 625 KB

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National Insurance guidance for software developers (2022 to 2023) — effective from 6 July 2022

ODT, 618 KB

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National Insurance guidance for software developers (2022 to 2023) — effective from 6 April 2022 to 5 July 2022

ODT, 616 KB

This file is in an OpenDocument format

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National Insurance guidance for software developers (2021 to 2022)

ODT, 562 KB

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Details

Technical specifications giving National Insurance calculation methods and guidance for payroll software developers.