Rex says
Money math without the spreadsheet headache. Plug in your numbers and I'll show you exactly where the dollars land.
Try a scenario
Click to load — tweak from there.Inputs
Result
Fixed cost covered by retainers
61.5%
Monthly retainer revenue
$45,500
Recurring share of total revenue
46.7%
Extra retainers to reach full coverage
4.4
Monthly coverage gap
$28,500
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Got your number — what next?
Pick one, it takes 20 secondsHow to use this
- 1Enter number of active retainers.
- 2Enter average retainer per month ($).
- 3Enter project revenue per month (average) ($).
- 4Enter monthly fixed cost base ($).
- 5Read your fixed cost covered by retainers on the right — it updates as you type.
- 6Hit Share to keep the scenario or send it to someone.
About this calculator
Recurring retainer revenue is worth more than the same dollar of project revenue because it's predictable, cheaper to service, and it's what buyers pay a multiple for. This calculator splits your book into retainer and project revenue, calculates the share of your monthly cost base covered by retainers alone, and shows how many additional retainers of a given size you'd need to reach full coverage. Agencies that cover 100% of fixed cost with retainers can treat project work as pure upside and stop making desperate pricing decisions in slow quarters — it's the single structural change that most improves both margin and valuation multiple.
Worked example
Using the values the calculator loads with:
Inputs
- Number of active retainers: 7
- Average retainer per month: 6500 $
- Project revenue per month (average): 52000 $
- Monthly fixed cost base: 74000 $
Results
- Fixed cost covered by retainers: 61.5%
- Monthly retainer revenue: $45,500.00
- Recurring share of total revenue: 46.7%
- Extra retainers to reach full coverage: 4.4
- Monthly coverage gap: $28,500.00
What each field means
Inputs
- Number of active retainers
- The number of active retainers used in the calculation. Starts at 7 so you have a working example on load.
- Average retainer per month ($)
- The average retainer per month used in the calculation, measured in $. Starts at 6500 $ so you have a working example on load.
- Project revenue per month (average) ($)
- The project revenue per month (average) used in the calculation, measured in $. Starts at 52000 $ so you have a working example on load.
- Monthly fixed cost base ($)
- The monthly fixed cost base used in the calculation, measured in $. Starts at 74000 $ so you have a working example on load.
Results
- Fixed cost covered by retainers
- Returned as a percentage and shown as the headline result. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Monthly retainer revenue
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Recurring share of total revenue
- Returned as a percentage. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Extra retainers to reach full coverage
- Returned as a decimal number. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Monthly coverage gap
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
FAQ
Why does retainer coverage affect valuation?
Buyers discount lumpy project revenue heavily because it doesn't survive an owner transition reliably. Agencies with a high recurring share commonly transact at meaningfully higher EBITDA multiples than project shops of the same size and profitability.
Is 100% coverage the goal?
It's a strong position, but not the only one. Some high-margin project shops deliberately stay project-only and hold larger cash reserves instead. The failure mode to avoid is low coverage plus low cash, which forces bad pricing decisions.
How do I convert project clients to retainers?
Pitch the follow-through, not the maintenance: the optimisation, reporting, and iteration that makes the project investment pay off. Doing it in the final third of a successful project converts far better than doing it after the invoice clears.
Do retainers have worse margin?
Often slightly, because clients push for volume pricing — but delivery cost is usually lower too, since the team already knows the account and pre-sales cost is near zero on renewal. Measure margin per account rather than assuming.
Accuracy and limitations
- Results are estimates before tax, fees, and inflation unless an input explicitly covers them.
- Rates are treated as fixed for the whole period — variable-rate products will drift from this projection.
- This is educational maths, not financial advice. Check anything contractual with the lender or your accountant.
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Cite this calculator
Writing about this topic? Grab a citation — every link helps keep these tools free.
RevenueLab. (2026). Retainer vs Project Revenue Mix Calculator. Retrieved from https://www.revenuelab.fyi/toolbox/retainer-vs-project-mix
<p>Source: <a href="https://www.revenuelab.fyi/toolbox/retainer-vs-project-mix" target="_blank" rel="noopener">Retainer vs Project Revenue Mix Calculator — RevenueLab</a> (2026).</p>
Source: [Retainer vs Project Revenue Mix Calculator — RevenueLab](https://www.revenuelab.fyi/toolbox/retainer-vs-project-mix) (2026).