Skip to main content

Introduction

This guide outlines the scope and methodology for the calculation of taxes for the 2024-25 tax year, with a specific focus on the end-of-year finalisation process.

The document is intended for business analysts, software developers, and software testers developing software compatible with Making Tax Digital for Income Tax APIs.

Document structure

This document is structured to align with the tax calculation process:

  • defining income and benefits
  • applying allowances and reliefs
  • detailing the tax calculation process

Each section is further divided into relevant subsections that include:

  • description along with the relevant APIs used in the calculation
  • input parameters from the APIs and other related sections
  • other parameters referenced in the pseudocode
  • pseudocode outlining the step-by-step calculation process

Document changelog

2nd April 2025

Initial draft version published

September 2025

Full version published, along with downloadable config file

Getting help and support

If you have specific questions about this document or would like to provide feedback, please email SDSTeam@hmrc.gov.uk