Can I split one quote into multiple invoices?

Yes. Draft one master quote, then convert each stage into its own invoice as the work completes. Each invoice can carry its own faster payment link.

Does Fixxa work for MCS-registered heat pump installers?

Yes. Fixxa handles the quoting and invoicing side. MCS certification and BUS scheme paperwork stay with your MCS body.

How does VAT work on staged invoices?

You apply VAT per invoice at your default rate. If you are VAT-registered, each stage carries the VAT on that stage's value.

Standard Stripe payouts land in your bank within 2 business days. Same-day payouts are available at 1% (minimum 30p).

£19.99/month or £190/year (2 months free). 14-day free trial, no card needed.

For UK heating engineers

Invoicing app for UK heating engineers juggling installs, service calls and long-play upgrades

Big system upgrades take weeks. Service calls take an hour. Fixxa handles both without changing gear — dictate the job, split it into stages if you need to, and get paid on WhatsApp.

Start 14 day free trial, no card needed See pricing

Quick answer

Fixxa is a voice-first invoicing app for UK heating engineers. Dictate system upgrades, powerflushes, radiator swaps and heat pump installs. Quote in stages, invoice at each milestone, and send faster payment links on WhatsApp so cash flow does not stall on longer jobs.

Why heating engineers choose Fixxa

Built for UK heating and system engineers
Stage quotes and invoices for big install jobs
Voice-first dictation from the boiler cupboard
Faster payment links via WhatsApp
MTD-ready digital records baked in
£19.99/month, £190/year, 14-day free trial

How it works

1. Quote the whole job

Dictate design, first fix, second fix, commissioning. Fixxa builds a staged quote the customer can approve on their phone.

2. Invoice at each milestone

Turn each approved stage into an invoice as work completes. Deposit up front, second fix mid-job, final on sign-off.

3. Get paid stage by stage

Card payment link on every invoice. Cash flow doesn't wait until the final week of a 4-week install.

Key benefits

Staged pricing for staged work

Break long installs into deposit, first fix, second fix and completion. Customers understand the schedule, you get paid as you go.

Radiator upgrades priced properly

Save common rad sizes and TRVs as line items. A 12-rad upgrade quote takes 90 seconds instead of an evening.

Heat pump quotes look the part

A £14k ASHP install needs paperwork that matches. Branded quotes with each element itemised win more MCS work.

MTD-ready

Every stage invoice is a digital record. Your MTD quarterly totals build themselves.

Built for heating engineers

Full central heating installs and upgrades
Powerflushes and system cleans
Radiator and TRV upgrades
Air source heat pump installs
Underfloor heating first and second fix
Commercial plant room maintenance

Real heating engineers jobs, quoted by voice

Full system upgrade, 4-bed

Quote in three stages: strip out and rough-in, boiler and rads fitted, commissioning. Send stage invoices at each sign-off so the customer never sees a single big bill.

Powerflush on existing system

Standard line items for prep, flush, inhibitor, magnetic filter and test. Send the invoice with a before/after sludge photo — customers pay quicker when they see the value.

12-rad upgrade with TRVs

One line per room, TRVs itemised separately. Deposit invoice for the rads, balance on completion.

ASHP install with grant

Line-itemise design, MCS survey, unit, cylinder, install and commissioning. Attach paperwork the customer's BUS grant application needs.

Common quoting and invoicing mistakes

One big invoice at the end of a long install

Cash flow dies waiting for it. Stage invoicing means money in every 7 to 10 days.

Not itemising materials mark-up

Show materials at your supply price. Your labour rate carries the margin. Customers question one lump-sum figure, not itemised parts and labour.

Forgetting to invoice for commissioning

It is billable time. Add it as a line, don't roll it into 'labour'.

No deposit on ASHP jobs

Kit is expensive and lead times are long. Deposit invoices with card links get money in before the crate arrives.

Practical workflow tips

Standardise your stage names (design, first fix, second fix, commissioning) so quotes stay consistent
Save common part codes for TRVs, thermostats and cylinders
Photo the completed install and attach to the final invoice on WhatsApp
Reconcile payouts weekly so material spend and revenue line up cleanly

Trust and compliance

MCS accreditation, Gas Safe registration, F-Gas certification and BUS scheme paperwork remain the engineer's responsibility. Fixxa handles the quoting, invoicing and payment side around those regulatory documents.

Simple pricing

Fixxa is £19.99/month or £190/year (2 months free). Includes voice quoting and invoicing, faster payment links, reminders and exports. 14-day free trial, cancel anytime. See full details on the pricing section.