HMRC has developed Application Programming Interfaces (APIs) for submitting Interest Restriction Returns (IRR) and for reporting company appointments and revocations under the Corporate Interest Restriction (CIR) legislation. This is available for use from July 2021. The APIs can be found on the HMRC Software Developers Hub.

The UK’s CIR took effect from 1 April 2017 and potentially applies to corporate entities. It aims to restrict a group’s deductions for interest expense and other financing costs for corporation tax to an amount that is commensurate with taxed UK activities, which also takes into consideration how much the group borrows from third parties such as banks and other finance options. Further information can be found on how to submit a Corporate Interest Restriction return and the restriction on Corporation Tax relief for interest deductions on GOV.UK.

Software developers have been provided with a roadmap to begin updating their products. The existing service will run in parallel with the APIs until April 2022; at which time HMRC will be seeking to mandate the use of APIs for submission of IRRs and reporting company appointments and revocations. The current functionality will therefore be switched off, and companies and agents will no longer be able to submit through alternative routes, such as email or with company tax returns. HMRC is seeking feedback on this change.