Septic & well
Septic Service Pricing Calculator
Prices septic work from cost upward, in a trade where equipment and disposal make overhead unusually heavy.
Result
Overhead and margin are taken as shares of the selling price, which is why the cost is divided rather than multiplied. Adding 15% to cost does not produce a 15% margin. Gross profit is what is left after the cost of doing the job. Overhead comes out of that: the building, the office wages, the vans, insurance, software and advertising. A healthy gross margin still loses money if overhead is larger.
Get a Free Business AuditHow the calculation works
Direct cost is divided by one minus overhead and margin together, which is what makes the price carry both rather than layering one on the other. The reason this matters more in septic work than in a lighter trade is that the overhead is genuinely large. A vacuum truck, an excavator and a trailer are financed, insured, registered, maintained and depreciating whether or not they leave the yard, and disposal fees are a real per-job cost that does not look like overhead but behaves like one if you forget to bill it. An overhead rate calculated from a lighter trade's assumptions will underprice this work substantially.
What moves the number
- Equipment ownership cost, which is the dominant overhead item and accrues by the month rather than the job.
- Disposal fees and haul time, which have to be recovered per job and vary with distance.
- Utilisation, since a truck that works three days a week has to recover the same monthly cost across fewer jobs.
- Seasonality, because frozen or saturated ground stops work and the equipment payments continue.
Where this one goes wrong
The markup and margin distinction is the expensive one here, as everywhere: dividing by one minus the margin is not the same as multiplying by one plus it, and the second underprices. Beyond the arithmetic, the specific trap in this trade is treating equipment as a job cost rather than as overhead that has to be recovered across a year including the weeks it cannot work. Winter and wet season downtime is real and the payments are not seasonal. Price against your actual working weeks rather than a full calendar, or the busy season subsidises a shortfall you never accounted for.
Before you quote
- Build the overhead rate from equipment ownership across a realistic working year.
- Recover disposal fees and haul time per job rather than absorbing them.
- Check the resulting margin against the markup figure so the two are not confused.
Questions
About this calculator
Why is septic work priced higher than general plumbing?
Equipment. A vacuum truck and an excavator carry financing, insurance, registration and maintenance whether or not they work that day, and disposal carries a real per-job fee. That overhead has to be recovered across the jobs you actually do, and it is far heavier than a service van.
Should disposal be a separate line or inside the price?
Either works provided it is genuinely recovered, and separating it makes the variation with distance defensible. What causes losses is treating it as incidental, since a long haul to an approved site can be a significant share of the job's cost and is invisible in an hourly rate.
How do I set an overhead rate for equipment heavy work?
Total the annual cost of owning and running the equipment, including finance, insurance, registration, maintenance and depreciation, then divide across the revenue you realistically expect in your actual working weeks. Using a full calendar year overstates the weeks available and therefore understates the rate.
The formula
price = direct cost / (1 - overhead% - margin%)
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How to use this calculator
- Labour cost ($). Burdened: wages plus tax, insurance and the vehicle, not the hourly wage.
- Materials cost ($). Enter your own figure; the page starts at $120.
- Other direct costs ($). Permits, disposal, equipment hire, subcontractors.
- Overhead rate (%). Overhead as a share of revenue. Work it out from last year's accounts.
- Target net margin (%). Enter your own figure; the page starts at 15%.
The result updates as you type, so you can try a figure, see what it does to price to quote, and change it back. Nothing you enter is sent anywhere or saved.
A worked example
These are the figures the calculator opens with. Every number in the results column below is produced by the same calculation the page runs, so you can follow it through before putting your own figures in.
What goes in
| Input | Value |
|---|---|
| Labour cost | $340 |
| Materials cost | $120 |
| Other direct costs | $0 |
| Overhead rate | 22% |
| Target net margin | 15% |
What comes out
| Result | Value |
|---|---|
| Price to quote main result | $730.16 |
| Direct cost | $460 |
| Overhead recovered | $160.63 |
| Net profit | $109.52 |
| Gross margin | 37.0% |
| Markup on direct cost | 58.7% |
Quote $730.16 to cover $460 of direct cost, recover $160.63 of overhead and leave $109.52 of net profit. That is a 58.7% markup on cost.
How sensitive the answer is
Holding everything else steady and changing only labour cost, this is what happens to price to quote. It is worth knowing which of your inputs the answer actually hinges on, and which barely move it.
| Labour cost ($) | Price to quote |
|---|---|
| $170 | $460.32 |
| $255 | $595.24 |
| $340 example above | $730.16 |
| $510 | $1,000 |
| $680 | $1,270 |
Every other input is held at the example value while this one changes, which is not how a real job behaves. Treat it as a guide to which number matters most, not as five separate quotes.
What each figure means
- Labour cost ($)
- Burdened: wages plus tax, insurance and the vehicle, not the hourly wage.
- Materials cost ($)
- A money amount, starting at $120.
- Other direct costs ($)
- Permits, disposal, equipment hire, subcontractors.
- Overhead rate (%)
- Overhead as a share of revenue. Work it out from last year's accounts.
- Target net margin (%)
- A percentage, between 0 and 80, starting at 15%.
What the results tell you
| Result | What it is |
|---|---|
| Price to quote | The headline result. A money figure. |
| Direct cost | A money figure. |
| Overhead recovered | A money figure. |
| Net profit | A money figure. |
| Gross margin | A percentage. |
| Markup on direct cost | A percentage. |
Estimating is the easy part
The jobs you never hear about cost more than the ones you mis-measure. BDEVY builds the marketing, systems and automation that bring them in.