HMRC VAT431NB DIY Housebuilder VAT Refund: Fill In

What is HMRC VAT431NB DIY housebuilder refund?

Under HMRC's DIY housebuilders scheme, you can reclaim the VAT you paid on building materials used to build a new home, or to fit out a building shell. HMRC takes the claim through its online service, and on form VAT431NB by post if you can't use it.

The form starts with nine questions that check you are eligible, then asks for your details and bank account, the property, and every invoice: Table A for invoices that show the VAT separately and Table B for those that don't. It ends with a checklist of the documents to send and the declaration.

FileIt asks the eligibility questions first, lets you type or paste your invoices one per line (straight from a spreadsheet), adds up the VAT and prints everything on HMRC's own PDF. You sign it and post it. FileIt never sends anything to HMRC.

Who fills it: A DIY housebuilder claiming VAT back on building materials for a new house
Sent to: BT&C VAT, HM Revenue and Customs, BX9 1WR, by post (HMRC offices don't accept hand-delivered claims)
Time limit: 3 months after completion for buildings completed before 5 December 2023; 6 months for those completed on or after it
Invoices: Up to 50 in Table A and 50 in Table B
Edition: HMRC 11/23
Pages: 11

Who needs to fill out HMRC VAT431NB DIY housebuilder refund?

Self-builders who built a new house to live in themselves or for relatives.
People who bought a building shell and fitted it out to make a home.
Joint claimants, such as a couple building together.
Charity builders constructing a building for the charity's own purposes.

When to use HMRC VAT431NB DIY housebuilder refund

Once the building is complete and you have the completion certificate or other accepted evidence.
Within the time limit: 3 months after completion before 5 December 2023, 6 months from that date. Outside it, attach a letter explaining why.
When you can't use HMRC's online claim service.

What you need before you start

Planning permission (full, or outline plus approval of reserved matters) and the approved building plans.
The building regulation completion certificate (or proof of habitation) and the certified completion date.
Every invoice for allowable building materials: number, date, description, supplier, supplier's VAT number, total and VAT.
Your National Insurance number, contact details and the bank account for the refund.
A form 64-8 or letter of authority if an agent deals with HMRC for you.

What’s on HMRC VAT431NB DIY housebuilder refund

The 2023 edition has 11 pages. FileIt asks for it in 10 parts, and it is signed by Claimant:

Questions 1 to 9 — is your build eligible?Claimant
Personal detailsClaimant
Bank or building society detailsClaimant
Agent details or third party authorityClaimant
Details of your new build propertyClaimant
Table A — invoices where the VAT is shown separatelyClaimant
Table B — invoices where the VAT is not shown separatelyClaimant
Summary of VAT claimedClaimant
Checklist — documents you are sendingClaimant
DeclarationClaimant

How to fill out HMRC VAT431NB DIY housebuilder refund, step by step

1 Questions 1 to 9: eligibility

A new build, or a shell you fitted out; approved plans; planning permission and any condition on separate use; a completion certificate and its date; any other buildings in the claim. The form says to stop if these show you aren't eligible.

2 Personal details

Your name, contact details, NI number and address, the building's address if different, when you moved in, whether you or relatives will live there, any other claimant, and any link to a VAT-registered business.

3 Bank, agent and property

The account for the refund, any agent, and the building's type, storeys and rooms, including a garage.

4 Your invoices

Table A lists invoices that show the VAT separately, Table B those that don't. Explain any invoice that isn't in your name. FileIt totals the VAT for lines 34, 37, 38 and 39.

5 Checklist and declaration

Tick the documents you are enclosing (copies, not originals), confirm the declaration and sign.

Common mistakes to avoid

Sending original documents. HMRC can't return them, so send copies.
Including items that aren't allowable. Check HMRC's guidance on goods and services you can claim for first.
Leaving out the completion certificate, planning permission or plans, which can delay or stop the claim.
Claiming after the time limit without a letter explaining why.
Invoices not in your name with no explanation.

After you fill it out

Sign the declaration and post the claim with copies of your documents.

HMRC will tell you which invoices it wants to see.

Keep your original invoices and certificates safe. FileIt keeps the claim in your vault with them.

Fill out HMRC VAT431NB DIY housebuilder refund online with FileIt

Pick the person. Choose someone from People and FileIt fills in their name, date of birth, address and other details it already knows.
Answer plain-language questions. One part of the form at a time, with the official help text beside each question — 79 fields in all. Your answers save as you go.
Check the live preview. Watch your answers land on the real HM Revenue & Customs (HMRC) form, and let FileIt do any worksheet arithmetic.
Generate the official PDF. FileIt prints your answers into the agency’s own PDF and files it in that person’s folder in your vault. Sign it, or send it for e-signature.

FileIt fills the form — it never files or submits anything for you. Deliver the finished form to whoever asked for it, the way the form’s instructions say.

Start HMRC VAT431NB DIY housebuilder refund now — it’s free

HMRC VAT431NB DIY housebuilder refund: frequently asked questions

Can I claim online instead?

Yes. HMRC has an online service for DIY housebuilder claims; the VAT431NB is for those who can't use it.

Do I attach my invoices?

Not at first. You list them on the form and HMRC contacts you about which ones it needs.

What if I have more than 50 invoices in a table?

The form has room for 50 in each table. Use HMRC's online service, or attach a continuation sheet for the rest.

Is this the form for conversions?

No. VAT431NB is HMRC's claim form for new houses.

Does FileIt submit the claim?

No. FileIt prepares HMRC's PDF; you sign and post it.

Official sources

Blank form (PDF), published by HM Revenue & Customs (HMRC): https://assets.publishing.service.gov.uk/media/65858474fc07f300128d46e8/VAT431NB.pdf
Official instructions and guidance: https://www.gov.uk/guidance/claim-a-vat-refund-for-a-new-home-or-charity-building-if-youre-a-diy-housebuilder
Edition shown on this page: VAT431NB HMRC 11/23 (checked 2026-10-25).

FileIt is not affiliated with or endorsed by HM Revenue & Customs (HMRC) or any government. This page explains the form in general terms and is not legal, tax or immigration advice. Always read the official instructions, and check that you are using the edition the recipient accepts. Page last reviewed 2026-10-25.