Backflow Testing Invoicing App (2026)
Backflow testing is billed per device, on an annual cycle, with separate lines for repairs, retests, and the water authority's filing fee. ShowTheReceipts ($15/mo) saves per-device test rates and repair lines, invoices multi-device properties in one pass, takes card payment at the meter, and sets next year's test before you leave.
How we picked
Entry-plan prices as published in 2026, taken from each vendor's own pricing page or a recent third-party summary. Judged on the one-person tester's workflow — per-device billing, annual recurrence, repair and retest lines, pass-through filing fees, and payment on site — not on municipal report-submission portals or utility-side compliance tracking, which are a separate category of tool.
| Software | Starting price | Best for |
|---|---|---|
| ShowTheReceipts That's us | $15/mo | Solo testers: per-device rates, annual cycles, retest and repair lines, card at the meter |
| Invoice2go | $9.99/mo+ | Basic mobile invoicing |
| Wave | Free / $16/mo | Free invoicing with light bookkeeping |
| Kickserv Flex | $19/mo | Budget scheduling with invoicing |
| ServiceTitan | Quote only | Large plumbing companies with dispatch teams |
One device, one trip, one renewal
Backflow testing is about as clean as recurring revenue gets in the plumbing trades — an annual requirement, a short visit, a device that’ll need you again next year at the same address.
The whole business really comes down to whether you can get through a route efficiently and be the one who calls first.
1. ShowTheReceipts — $15/mo
Per-device test rates, repair and retest lines, filing fee as a pass-through, card payment at the meter, next year scheduled on the spot.
2. Invoice2go — $9.99/mo+
Basic mobile invoicing.
3. Wave — Free / $16/mo
Free invoices with light bookkeeping.
4. Kickserv Flex — $19/mo
Budget scheduling with invoicing.
5. ServiceTitan — quote only
Built for large plumbing operations running dispatch teams and call centers.
The lines a backflow invoice needs
- Test, per device — by assembly type and size
- Site minimum or trip charge
- Repair labor — with parts itemized
- Repair kit / parts — by assembly
- Retest after repair
- Water authority filing fee — pass-through, at cost
- Confined space or vault entry — surcharge
- Emergency or same-day — its own rate
Failed devices are the margin
A pass is a fifteen-minute visit at a modest price. A failure means a repair, parts, and a retest, and that’s really where a route’s revenue comes from.
Quote the repair on the spot, state your retest policy, and most customers approve it before you’ve even packed up the gauge.
Own the calendar
Whoever schedules next year’s test first keeps the account. Set the recurrence on site and the renewal pretty much handles itself, well before the utility’s notice ever lands in the customer’s mail.
Frequently asked questions
How should backflow testing be priced?
Per device, with a site minimum. A property with six assemblies is one trip and six tests; a single residential irrigation device is one trip and one test, which is exactly why the minimum exists.
How do I bill the water authority's filing fee?
As a separate pass-through line at cost, labeled as the authority's fee. Burying it in your test price makes your price look high and makes the fee look like yours when it changes.
Should a retest after repair be free?
Not automatically. If you did the repair, a bundled retest is a reasonable courtesy; if someone else did, charge the retest. Either way, decide it once and put it on the quote so it isn't negotiated in the driveway.
How do I stop losing the annual renewal?
Schedule the next test on the day you finish this one. Backflow is pure recurring revenue and the tester who reminds the customer first keeps the account — the work almost never changes hands for price.