With the illustrative inputs below, the result is 4 months.
Try this with your own numbersFormula and worked example
Payback months = acquisition cost / monthly contribution
| Input | Example |
|---|---|
| Acquisition cost per customer | 300 |
| Monthly contribution per active customer | 75 |
| Calculated result | 4 months |
Choose reliable inputs
Plan materials, travel and crew time before committing to a price. For this plumbing service calculation, use a completed job sheet, supplier quotes and a crew schedule and a consistent definition of one service visit.
- Fittings: include the portion belonging to this service visit or reporting period, and record where the value came from.
- Access time: include the portion belonging to this service visit or reporting period, and record where the value came from.
- Travel: include the portion belonging to this service visit or reporting period, and record where the value came from.
Use the same currency for every money input. Do not mix weekly costs with monthly revenue, or count the same expense in both an itemised cost and allocated overhead.
What if customers leave before payback?
Acquisition may never be recovered. Compare this estimate with measured retention and include delivery costs in contribution.
Assumes constant contribution and continued customer activity throughout payback.
What if this input changes?
If acquisition cost per customer rises by 10%, this example changes by 0.4 months. This shows the effect of one change; it does not predict what will happen.
Open the calculator, save your baseline, then change the input supported by the least reliable estimate in your records. Compare both scenarios before committing to a price or capacity promise.