Hourly billing is not evil, and there are jobs where it is genuinely the fairer structure. But for the standard residential work that makes up most plumbing callouts, fixed pricing protects you better, and here is the honest reasoning from a business that quotes fixed.
Fixed price vs hourly: how the risk moves
| Situation | Fixed quote | Hourly rate |
|---|---|---|
| Job runs longer than expected | Plumber absorbs it | You pay for every extra hour |
| Job finishes early | Plumber benefits | You benefit |
| Scope is clear (drain clear, tap, hot water swap) | Ideal | Unnecessary risk for you |
| Scope is genuinely unknown (exploratory, hidden damage) | Hard to quote honestly | Can be fair with a cap and check-ins |
| Slow worker | Your price does not change | Your price climbs |
| Comparing plumbers | Easy, number vs number | Nearly impossible |
| Example with us | Drain clear $250 to $400; tap repair $80 to $180 plus parts; toilet repair $120 to $300 | We do not bill residential work by the hour |
Why does fixed pricing usually protect the homeowner?
Because it moves the risk of the unknown onto the person best placed to judge it. A plumber quoting fixed has to assess the job properly, commit to a number, and wear it if the job fights back. On hourly, every complication, every parts run, and every slow patch lands on your bill, and you have no practical way to audit how the hours were spent. Fixed pricing also makes plumbers comparable: three fixed quotes for the same toilet replacement can be judged side by side, while three hourly rates tell you almost nothing because the fast tradie at a higher rate routinely beats the slow one at a lower rate. That is exactly why we publish fixed bands like $250 to $400 for a machine drain clear and $350 to $750 plus the suite for a toilet replacement, and why we will not quote you an hourly figure.
When is hourly billing actually fair?
When nobody, including the plumber, can honestly define the scope in advance. Genuine exploratory work, like chasing an intermittent fault through an old and heavily modified system, or strata jobs where the plumber is directed task to task, can be fair on time-based billing. Even then, a fair hourly arrangement has three features: a written rate agreed up front, an agreed cap or check-in point where work pauses for your approval, and an itemised record of what was done in the time. If an hourly proposal comes without those three protections, treat it as a blank cheque, because that is functionally what it is. Our own approach on genuinely unknowable jobs is different: we inspect first, often with a camera, then convert the unknown into a fixed quote before the real work starts.
How does scope creep happen on hourly jobs?
Rarely through dishonesty, mostly through drift. The job uncovers a second issue, the plumber fixes it because they are already there, a parts run takes forty minutes, and the invoice arrives at double the verbal estimate with every line technically justified. On a fixed quote that drift cannot touch you, because any additional work needs a new agreed price before it happens. The question that kills scope creep on any pricing model is the one we suggested on our hiring checklist page: "What is the final figure, and what specifically would change it?" Get the answer in writing.
What should I ask for before saying yes?
A written fixed price, the conditions that would vary it, the warranty terms, and the licence number. If a plumber says the job cannot be fixed-priced, ask why. Sometimes the answer is legitimate, and a paid inspection that converts to a fixed quote, like our CCTV drain inspections at $200 to $350, is the honest middle path. Sometimes the answer is that they would simply rather you carried the risk. You are allowed to decline that.
Want a real fixed price instead of an open-ended estimate? Call Hills Plumbing & Gas on 0472 657 042 or book through our Blocked Drains service page. The price we quote is the price you pay.