Guide · United Kingdom
If you are building or converting a home in the UK under HMRC's DIY housebuilders' scheme, the claim (often associated with form VAT431NB) lives or dies on invoices. This guide is informational: how to keep a reclaim-ready schedule while you build, and where ConstructionPro.io fits as an invoice log — not as your accountant or HMRC.
Not tax advice. Rules, eligibility and deadlines change. Always follow GOV.UK: Reclaim VAT on a self build home and take advice from HMRC or a qualified accountant before you claim.
According to GOV.UK, you can apply for a VAT refund on building materials and services if you are:
This is the DIY housebuilders' scheme. GOV.UK states you can only make one claim for a VAT refund under the scheme, and deadlines depend on when the work finished (three or six months after completion — check the live GOV.UK page). The claim process differs by what you are building; use HMRC's guides, not this page, for eligibility detail and the current VAT431NB / online claim steps.
This reclaim route is a UK scheme. ConstructionPro does not invent equivalent US or EU reclaim workflows. Our grant finder shows grants for the market you choose for each project: UK profiles can surface DIY VAT as a funding theme, while US, EU and Ireland projects get grants for their own market.
HMRC asks for evidence. Weak paperwork — not “how hard you worked” — is what sinks DIY reclaim packs. Patterns we see on builds:
Bills made out to a contractor, relative, or limited company that is not the claimant often fail. Align the invoice name with who is claiming under the DIY scheme.
If VAT is not shown (or not stored), you cannot show what was charged. Zero-rated or outside-scope lines need to be obvious — do not invent figures.
Paying from the bank on Tuesday does not rewrite the invoice date. A schedule that only has payment dates fights the documents at claim time.
Reconstructing a multi-year build from photos and WhatsApp in the last fortnight before the deadline is how lines go missing.
Aim for a schedule you could hand to an accountant without reconstructing history from memory. Per invoice, capture at least:
Must match who charged you. Nickname the tradesperson in your head if you like — store the legal name from the bill.
If the document shows a VAT number, keep it with the invoice. Missing numbers are a common reclaim headache.
When the bill splits them, record all three. Your project spend still uses the gross you pay; the split is for the claim pack and your accountant.
Cash date and invoice date are not the same. Keep both if they differ so the schedule matches the paperwork HMRC expects.
Tag the budget category and keep everything on the one self-build project. Mixed “misc” piles are hard to defend at completion.
Recording net / VAT / gross on the bill is separate from how the budget spends. In ConstructionPro, spend still posts the gross. See the product how-to Record net, VAT and gross on an invoice — that article is about the ledger fields, not filing VAT431NB.
Self-builds span months or years. The reclaim window after completion is short (see GOV.UK for the current three- or six-month rule). If every PDF still lives in email and every VAT figure is “somewhere on the photo”, you will spend the deadline window hunting documents instead of checking them.
A running invoice schedule — supplier, dates, net / VAT / gross, category, job — means completion is an export and a review, not an archaeology project. Keep the original PDFs or photos alongside the rows; the schedule is the index, not a substitute for the documents HMRC may want to see.
ConstructionPro.io is a live-build ledger for budget, invoices, quotes, cash flow and programme. For DIY reclaim prep it helps you:
We do not file VAT431NB for you, calculate your reclaim total as tax advice, or replace HMRC. There is no in-product chat thread for invoices — comments stay on the invoice. CSV export is how you leave with your data; accounting integrations are not live.
Related product pages: Invoice processing, Self-build homeowners, UK market.
Disposable demo with a house ledger — log invoices, categories and VAT fields. Opens with the Self-Build persona. We do not file your HMRC claim.