Collection

Corporation Tax online: support for software developers

Find technical specifications for software developers working with the Corporation Tax online service.

• From: HM Revenue & Customs
• Published: 1 January 2014

This collection brings together a list of technical specifications for software developers working with the Corporation Tax online service.

CT600

• Corporation Tax technical specifications: CT600 appendices
  • 17 May 2023
  • Guidance

CT600 RIM artefacts

• Corporation Tax technical specifications for CT600 RIM artefacts
  • 7 April 2026
  • Guidance

CT600 valid XML samples

• Corporation Tax technical specifications: CT600 valid XML samples
  • 25 January 2023
  • Guidance

Generic

• Corporation Tax generic technical specifications
  • 13 June 2025
  • Guidance

Local Test Service

• Local Test Service and LTS update manager
  • 15 January 2026
  • Guidance

XBRL and iXBRL

• Corporation Tax technical specifications in XBRL and iXBRL format
  • 15 May 2026
  • Guidance