VAT656VAT Notice of Amendment of Assessment

HMRC's manual says form VAT656 consists of three parts: a Notice of Amendment of Assessment, a Summary of assessment, and Assessment details by period.

“The procedural guidance in this manual only covers the VAT Mainframe and VISION processes. … Form VAT656 consists of three parts … Notice of Amendment of Assessment … Summary of assessment … Assessment details by period”

HMRC manual VAEC9060: VAT Amendments, Form VAT656 · checked 14 October 2026

In its section on form VAT656, HMRC's VAT Assessments and Error Correction manual says its procedural guidance only covers the processes it calls VAT Mainframe and VISION, and points to separate guidance for fully migrated customers (Making Tax Digital for VAT).

“Form VAT656 … The procedural guidance in this manual only covers the VAT Mainframe and VISION processes. For guidance on the Making Tax Digital and ETMP processes for fully migrated customers”

HMRC manual VAEC9060: VAT Amendments, Form VAT656 · checked 14 October 2026

The VAT Mainframe was retired in 2024, says HMRC's VAT Assessments and Error Correction manual (the manual that includes the VAT656 pages), and the VAT Legacy Data Store (VLDS) has replaced VISION as the repository for legacy VAT data.

“The VAT Mainframe was retired in 2024. Consequently, the VAT Legacy Data Store (VLDS) has replaced VISION as the repository for legacy VAT data.”

HMRC manual VAEC0150: Introduction: Where to go for advice · checked 14 October 2026

HMRC's manual section on issuing VAT656 says the trader's copy of the output documents is placed in an envelope together with a copy of the VAT34 Assessment Notes and sent to the trader.

“The procedural guidance in this manual only covers the VAT Mainframe and VISION processes. … Issuing VAT656 … The trader’s copy of the output documents should be placed in an envelope together with a copy of the VAT34 Assessment Notes and sent to the trader by the VALID Team.”

HMRC manual VAEC9120: VAT Amendments, Issuing VAT656 · checked 14 October 2026

If you disagree with a VAT decision such as a VAT656, GOV.UK's guide to disagreeing with a tax decision says you can challenge some decisions about your tax bill (for example Income Tax, Corporation Tax, VAT), that HMRC will tell you in their decision letter what to do if you disagree, and that you usually have 30 days from the date of the decision letter to either appeal or accept a review.

“You can challenge some decisions about: … your tax bill (for example Income Tax, Corporation Tax, VAT) … HM Revenue and Customs (HMRC) will tell you in their decision letter what to do if you disagree. You usually have 30 days from the date of the decision letter to either appeal or accept a review.”

GOV.UK: Disagree with a tax decision or penalty · checked 14 October 2026

For questions about the VAT656, HMRC's VAT helpline (GOV.UK) is 0300 200 3700, Monday to Friday, 8am to 6pm. GOV.UK says to call only if you cannot find the answer using the online guidance or services, and has a “Find out about call charges” link.

“Only call HMRC if you cannot find an answer to your VAT question using our online guidance or services. … Telephone: 0300 200 3700 … Opening times: Monday to Friday, 8am to 6pm. … Find out about call charges”

GOV.UK: VAT: general enquiries · checked 14 October 2026