Invoice app for gas engineers in London
Your Gas Safe number on every PDF. CP12 landlord certificates by voice note. Receipts, tax, MTD — same WhatsApp chat.
£29.99/mo · 7 days free · no card needed
Start Free on WhatsAppA real London gas engineer’s voice note:
"Mrs Davies, Chelsea London, annual boiler service, one-twenty plus parts forty-five."
What gas engineers in London actually have to log on a job
- Gas Safe number & ACS classes — Auto-prefixed on every invoice with your in-date ACS class numbers (CCN1, CENWAT, CKR1, HTR1, MET1, etc.).
- CP12 / Landlord Gas Safety Records — Issued in 30 seconds from a voice note and stored against the property.
- Gas tightness / let-by / standing pressure — Logged as an invoice note for audit.
- Boiler installation notification — Building Regs notification reference attaches with the invoice.
- Annual service reminders — 12-month auto-reminder to chase recurring revenue from the same customer.
What gas engineers in London actually deal with
Thames Water (most of the capital) or Affinity Water (north-west outskirts)
ULEZ — every day, every postcode. If your van is non-compliant, that’s £12.50 per working day on top of fuel.
32 London boroughs plus the City — Building Control is handled borough-by-borough, and Part P notifications vary by borough route.
Victorian terraces, ex-council flats, Georgian conversions, modern new-builds around Docklands and Stratford. Old lead pipework still common in pre-1970 stock.
Serving Chelsea, Hackney, Clapham, Islington, Camden and the rest of Greater London. Parking restrictions (red routes, controlled parking zones, school streets) and the congestion charge zone make a 20-minute job a two-hour billing situation.
London callout rates run £75–£120 vs £45–£80 for the rest of the UK. Materials cost the same but travel time and congestion eat the margin. Holdfort doesn’t set your prices — your rates are yours — but it stops you from losing track of what’s owed, what’s paid, and what’s been expensed along the way. All through WhatsApp. No app to install, no portal to log into.
Questions from London gas engineers
Yes. Speak the readings — standing pressure, working pressure, flue analysis — and Holdfort outputs a Gas Safe-format CP12 PDF that you sign on WhatsApp.
Yes — set once, prefixed on every quote, invoice, CP12 and service certificate, and Holdfort warns you 30 days before any class lapses.
Not as a separate line, but you can log them as receipts (photo the email or Dart Charge notice) and they’re captured as deductible vehicle expenses at tax time. Every charged day reduces your tax bill.
Yes — set your scheme (NICEIC, NAPIT, ELECSA, Stroma) once. Each invoice prints the scheme and your notification reference, which is what boroughs like Southwark and Lambeth ask for on Building Control self-certification.
They voice-note the invoice from inside the van before moving. Sixty seconds, invoice sent, and they’re out of the red route before the warden comes. It’s the main reason central-London trades signed up first.
Yes — quarterly-ready breakdowns and sole-trader categories. Required for self-employed earners over the MTD threshold from April 2026. See the MTD guide.
£29.99 per month, all in. 7 days free, no card needed to start. Founding-member price locked for life.
London gas engineer? Finish the job. Voice note the rest.
7 days free. 30 seconds to set up. Just WhatsApp.
Start Free on WhatsAppHold the fort. We’ve got the paperwork.