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3027 articles

personal-tax-mtd-quarter-periods-missing-guide

Personal Tax- MTD ‘Quarter periods missing’ guide

The FULL guide to the KB is linked here, as this is a quick checklist to help new users etc. The four quarters do not…

personal-tax-mtd-periods-are-incorrectly-ordered-2025-26

Personal Tax- MTD Quarter periods incorrectly ordered 2025/26

The MTD Quarter periods are incorrectly ordered on the Digital Tax Hub summary - This is a random visual issue coming from HMRC (since Summer…

personal-tax-client-agent-is-not-recognised-or-national-insurance-number-is-incorrect

Personal Tax- Client/Agent is not recognised OR National insurance number is incorrect

The "client or agent not authorised" error in IRIS Personal Tax for MTD or HMRC Data retrieval, this indicates that HMRC does not recognise your…

business-tax-zero-emissions-cars-box-726-must-not-be-completed-box-30-after-1-4-2025-and-1-4-2026

Business Tax- Zero Emissions Cars: Box 726 must not be completed box 30 after 1/4/2025 (and 1/4/2026)

IRIS Business Tax is currently following the HMRC schema rules which is creating the error etc and we cannot change this until an update from…

ias-personal-tax-work-out-the-basis-period-reform-transition-profit-in-2023-24

IAS Personal Tax – Work out the Basis Period Reform transition profit in 2023/24 onwards+ report changes

IAS Personal Tax has been updated to match the HMRC Basis Period Reform (BPR) transition profit calculations. If you wish to check the IRIS Personal…

personal-tax-employment-expenses-not-being-applied-on-tax-comp-etc

IAS24291 Personal Tax- Employment expenses not being applied on Tax comp etc 2025/2026

If you have certain Employment expenses entries and when you run the Tax computation: the Employment expenses are not deducting from the Employment income then…

business-tax-rd-box-653-is-incorrectly-ticked-for-ctap-start-before-01-04-2025-but-ended-after-31-03-2023

IAS23590 Business Tax- R&D Box 653 is incorrectly ticked for CTAP start before 01/04/2025 but ended after 31/03/2023

If you have updated to IRIS version 25.4.0.155 or have updated to the latest HOTFIXES in Dec 2025 but box 653 is still being ticked…

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PCSR – CS01 Rejection 12675 when one or more directors has a middle name

This rejection is occurring on submissions where one or more directors has a middle name. There will be a future service pack to resolve this…

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PCSR – CS01 Rejection 12677 when date of confirmation statement precedes 18/11/2025

This rejection is occurring on submissions where Date of confirmation statement is before 18/11/2025. This occurs because the tick box Include Officer Verification is missing…

ias23043-business-tax-rd-rdec-ct600-l55-tax-comp-incorrect-value-of-notional-tax-19-v-25

IAS23043 Business Tax- R&D RDEC CT600 L55/Tax Comp incorrect value of notional tax (19% v 25%)

If you have a CTAP period that starts prior to the start of the RDEC Merged Scheme. Therefore the calculation of notional tax should be…