The invoice app for UK builders.
Voice note in. Branded PDF invoice out — 15 seconds. Stage invoices, variations, CIS, tax — all through WhatsApp.
£29.99/mo · 7 days free · no card needed
Start Free on WhatsAppTry it in your head. A real builder’s voice note:
“Kitchen extension stage two for John, fourteen thousand, plus variation for the skylight two-fifty.”
Builders run multi-week, multi-month jobs with moving parts: subcontractors, material deliveries, variations, stage payments, CIS deductions, sign-offs. The paperwork is often where the margin evaporates. Holdfort treats each job as a single WhatsApp thread — the whole project’s cost plan, stage invoices, variations and running total in one place.
Common builders jobs on Holdfort
Kitchen and bathroom extensions
Budget at the start ("kitchen extension for John, 45 grand"), stage invoices as you go ("stage 1 deposit 9k", "stage 2 first fix 13.5k"), variations priced as they come. Running total updated automatically.
Loft conversions
Multi-month schedule with typical stages: strip-out, steels, roofing, first fix, second fix, bathroom, decoration, final. Each stage invoiced independently with cumulative total visible.
New-build and plot work
CIS deductions handled automatically if you’re a subcontractor — register the main contractor’s rate, Holdfort deducts on every invoice to that contractor. Gross and net visible in the chat.
Commercial fit-outs
Retail, office, hospitality refits with variations coming in faster than you can track. Each variation is a voice-note ("John wants an extra radiator, £280") and it gets added as a line to the current stage.
How builders actually use it day-to-day
The standard builder invoice pain is variations. You agreed £45,000 for a kitchen extension three months ago. Since then there’ve been six variations (another radiator, extra Velux, upgraded worktop, change of flooring, extra socket circuit, different tiles). Traditional approach: chase them up in a spreadsheet at month-end, invoice late, argue. Holdfort approach: voice-note each variation as it happens, customer signs it off in WhatsApp, it’s added to the next stage invoice automatically with the running total. Stage payments get paid faster because the customer can see exactly where the money’s going. For a builder doing £400k of projects a year, the effect on cashflow is substantial.
Questions builders ask us
Yes. Tell Holdfort the contractor’s CIS rate (20% verified, 30% unverified, 0% gross) when you set up the project and it auto-deducts on every invoice to that contractor. Running totals of gross invoiced, CIS deducted, and net paid are all visible in the chat. At year-end you get a CIS-ready CSV for your accountant to file the CIS300 reclaim.
That’s exactly what projects are for. Set up a £45k kitchen extension once at the start, then just say "stage invoice" as you hit each milestone. Budget, stages, variations, running total, final settlement — all tracked in one chat. You or the customer can see what’s been invoiced, what’s been paid, and what’s outstanding at any point.
Voice-note them as they happen: "John wants an extra radiator, £280, signed-off today". Holdfort adds it to the current project and prints it as a variation line on the next stage invoice. Customer sees it, you have a paper trail, you don’t get to the end of a project with ten variations that weren’t documented and a customer who thinks they’re covered by the original quote.
Project costings include a sub-cost line for each sub. When you receive a subcontractor’s invoice, photograph it — Holdfort reads it, logs the supplier, amount, VAT and CIS deduction (if applicable), and offsets it against the job’s running total. At the end you see your actual margin, not the one you hoped for at quote time.
£29.99/month, inc. VAT. 7 days free. No card to start. Founding-member price locked for life. See the pricing page.
No. Holdfort is WhatsApp — the one you already have. There’s nothing to install and no login to remember.
Yes. Quarterly-ready breakdowns, sole-trader categories, no spreadsheets. Ready for MTD for Income Tax from April 2026.
Finish the job. Voice note the details. Invoice done.
7 days free. 30 seconds to set up. Just WhatsApp.
Start Free on WhatsAppHold the fort. We’ve got the paperwork.