Act on the result
Set the retainer, overage rate and explicit included-scope and capacity boundaries.
Educational only: Business decision support, not accounting, tax or legal advice.
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Update policy: Reviewed when formulas or official dependencies change.
Scope: Market-neutral small-business planning using your own assumptions.
What this planner helps you decide
Best for
Service owners setting included scope, overage pricing and productive capacity for a monthly retainer.
Outputs
Monthly and annual fee, overage rate and revenue, margin, productive capacity and remaining hours.
Start here
Enter included and overage hours, loaded cost, overhead, utilisation, scope buffer, margins and monthly capacity.
Use a different tool when: Do not use this to compare fixed-fee and hourly economics; use Fixed Price vs Hourly Planner for that decision. Use this tool to set a sustainable monthly retainer.
Quote & capacity
Retainer Pricing: monthly and annual fee
Monthly and annual fee, overage rate and revenue, margin, productive capacity and remaining hours.
Amounts use the same currency as your inputs. No currency conversion is performed.
Retainer Pricing
Set included scope, overage pricing and capacity for a sustainable retainer. The scope buffer grosses delivery cost up by dividing by one minus the entered rate.
Your numbers stay in this browser
Monthly delivery hours included in the retainer.
Internal delivery cost.
Overhead assigned to the account.
Share of monthly capacity available for delivery.
Explicit protection for scope uncertainty.
Contribution retained from revenue.
Hours delivered beyond included scope.
Margin retained on overage work.
Total monthly team capacity.
Decision result
Every result is derived by the registered service and project engine.
PDF and CSV exports stay on this device. Clean page links contain no inputs.
- Delivery Cost
- 1,350/month
- Protected Delivery Cost
- 1,500/month
- Minimum monthly fee
- 2,307.69/month
- Annual Fee
- 27,692.31/year
- Included Capacity Hours
- 20 hours/month
- Productive Capacity Hours
- 32 hours/month
- Overage Rate
- 91.67/hour
- Overage Revenue
- 458.33/month
- Total Revenue
- 2,766.03/month
- Margin
- 35.8%
- Remaining Capacity Hours
- 7 hours/month
Scenario comparison
Each row names the assumption axis changed from the baseline.
ScenarioResultDifference
Current scenario2,307.69/monthBaseline
Lower Expected overage hours2,307.69/month+0/month (+0%)
Higher Expected overage hours2,307.69/month+0/month (+0%)
Save these results, change an input, then compare the updated figures with this baseline.
The baseline is temporary in this tab and is not added to shared scenario links or generated reports.
Calculation details
View calculation detailsView the formulas and inputs used for these results.
Delivery Cost
Delivery Cost
included hours × loaded cost + monthly overhead1,350/monthResult1,350/month
Reports/month from the entered project, capacity and ex-tax commercial assumptions. The engine retains full precision; presentation is bounded for readability.
Retainer Pricing Planner formulas →Inputs used by these formula steps
- Delivery CostIncluded Hours
- 20
- Delivery CostLoaded Cost Per Hour
- 55
- Delivery CostMonthly Overhead
- 250
- Delivery CostUtilisation
- 0.8
- Delivery CostScope Buffer Rate
- 0.1
- Delivery CostTarget Margin
- 0.35
- Delivery CostOverage Hours
- 5
- Delivery CostOverage Target Margin
- 0.4
- Delivery CostMonthly Capacity Hours
- 40
Protected Delivery Cost
Protected Delivery Cost
delivery cost ÷ (1 − scope buffer)1,500/monthResult1,500/month
Reports/month from the entered project, capacity and ex-tax commercial assumptions. The engine retains full precision; presentation is bounded for readability.
Retainer Pricing Planner formulas →Inputs used by these formula steps
- Protected Delivery CostIncluded Hours
- 20
- Protected Delivery CostLoaded Cost Per Hour
- 55
- Protected Delivery CostMonthly Overhead
- 250
- Protected Delivery CostUtilisation
- 0.8
- Protected Delivery CostScope Buffer Rate
- 0.1
- Protected Delivery CostTarget Margin
- 0.35
- Protected Delivery CostOverage Hours
- 5
- Protected Delivery CostOverage Target Margin
- 0.4
- Protected Delivery CostMonthly Capacity Hours
- 40
Minimum monthly fee
Monthly Fee
protected delivery cost ÷ (1 − target margin)2,307.69/monthResult2,307.69/month
Reports/month from the entered project, capacity and ex-tax commercial assumptions. The engine retains full precision; presentation is bounded for readability.
Retainer Pricing Planner formulas →Inputs used by these formula steps
- Monthly FeeIncluded Hours
- 20
- Monthly FeeLoaded Cost Per Hour
- 55
- Monthly FeeMonthly Overhead
- 250
- Monthly FeeUtilisation
- 0.8
- Monthly FeeScope Buffer Rate
- 0.1
- Monthly FeeTarget Margin
- 0.35
- Monthly FeeOverage Hours
- 5
- Monthly FeeOverage Target Margin
- 0.4
- Monthly FeeMonthly Capacity Hours
- 40
Annual Fee
Annual Fee
monthly fee × 1227,692.31/yearResult27,692.31/year
Reports/year from the entered project, capacity and ex-tax commercial assumptions. The engine retains full precision; presentation is bounded for readability.
Retainer Pricing Planner formulas →Inputs used by these formula steps
- Annual FeeIncluded Hours
- 20
- Annual FeeLoaded Cost Per Hour
- 55
- Annual FeeMonthly Overhead
- 250
- Annual FeeUtilisation
- 0.8
- Annual FeeScope Buffer Rate
- 0.1
- Annual FeeTarget Margin
- 0.35
- Annual FeeOverage Hours
- 5
- Annual FeeOverage Target Margin
- 0.4
- Annual FeeMonthly Capacity Hours
- 40
Included Capacity Hours
Included Capacity Hours
included hours20 hours/monthResult20 hours/month
Reports hours/month from the entered project, capacity and ex-tax commercial assumptions. The engine retains full precision; presentation is bounded for readability.
Retainer Pricing Planner formulas →Inputs used by these formula steps
- Included Capacity HoursIncluded Hours
- 20
- Included Capacity HoursLoaded Cost Per Hour
- 55
- Included Capacity HoursMonthly Overhead
- 250
- Included Capacity HoursUtilisation
- 0.8
- Included Capacity HoursScope Buffer Rate
- 0.1
- Included Capacity HoursTarget Margin
- 0.35
- Included Capacity HoursOverage Hours
- 5
- Included Capacity HoursOverage Target Margin
- 0.4
- Included Capacity HoursMonthly Capacity Hours
- 40
Productive Capacity Hours
Productive Capacity Hours
monthly capacity × utilisation32 hours/monthResult32 hours/month
Reports hours/month from the entered project, capacity and ex-tax commercial assumptions. The engine retains full precision; presentation is bounded for readability.
Retainer Pricing Planner formulas →Inputs used by these formula steps
- Productive Capacity HoursIncluded Hours
- 20
- Productive Capacity HoursLoaded Cost Per Hour
- 55
- Productive Capacity HoursMonthly Overhead
- 250
- Productive Capacity HoursUtilisation
- 0.8
- Productive Capacity HoursScope Buffer Rate
- 0.1
- Productive Capacity HoursTarget Margin
- 0.35
- Productive Capacity HoursOverage Hours
- 5
- Productive Capacity HoursOverage Target Margin
- 0.4
- Productive Capacity HoursMonthly Capacity Hours
- 40
Overage Rate
Overage Rate
loaded cost ÷ (1 − overage target margin)91.67/hourResult91.67/hour
Reports/hour from the entered project, capacity and ex-tax commercial assumptions. The engine retains full precision; presentation is bounded for readability.
Retainer Pricing Planner formulas →Inputs used by these formula steps
- Overage RateIncluded Hours
- 20
- Overage RateLoaded Cost Per Hour
- 55
- Overage RateMonthly Overhead
- 250
- Overage RateUtilisation
- 0.8
- Overage RateScope Buffer Rate
- 0.1
- Overage RateTarget Margin
- 0.35
- Overage RateOverage Hours
- 5
- Overage RateOverage Target Margin
- 0.4
- Overage RateMonthly Capacity Hours
- 40
Overage Revenue
Overage Revenue
overage hours × overage rate458.33/monthResult458.33/month
Reports/month from the entered project, capacity and ex-tax commercial assumptions. The engine retains full precision; presentation is bounded for readability.
Retainer Pricing Planner formulas →Inputs used by these formula steps
- Overage RevenueIncluded Hours
- 20
- Overage RevenueLoaded Cost Per Hour
- 55
- Overage RevenueMonthly Overhead
- 250
- Overage RevenueUtilisation
- 0.8
- Overage RevenueScope Buffer Rate
- 0.1
- Overage RevenueTarget Margin
- 0.35
- Overage RevenueOverage Hours
- 5
- Overage RevenueOverage Target Margin
- 0.4
- Overage RevenueMonthly Capacity Hours
- 40
Total Revenue
Total Revenue
monthly fee + overage revenue2,766.03/monthResult2,766.03/month
Reports/month from the entered project, capacity and ex-tax commercial assumptions. The engine retains full precision; presentation is bounded for readability.
Retainer Pricing Planner formulas →Inputs used by these formula steps
- Total RevenueIncluded Hours
- 20
- Total RevenueLoaded Cost Per Hour
- 55
- Total RevenueMonthly Overhead
- 250
- Total RevenueUtilisation
- 0.8
- Total RevenueScope Buffer Rate
- 0.1
- Total RevenueTarget Margin
- 0.35
- Total RevenueOverage Hours
- 5
- Total RevenueOverage Target Margin
- 0.4
- Total RevenueMonthly Capacity Hours
- 40
Margin
Margin
(total revenue − total cost) ÷ total revenue0.36 decimal rateResult35.8%
Reports decimal rate from the entered project, capacity and ex-tax commercial assumptions. The engine retains full precision; presentation is bounded for readability.
Retainer Pricing Planner formulas →Inputs used by these formula steps
- MarginIncluded Hours
- 20
- MarginLoaded Cost Per Hour
- 55
- MarginMonthly Overhead
- 250
- MarginUtilisation
- 0.8
- MarginScope Buffer Rate
- 0.1
- MarginTarget Margin
- 0.35
- MarginOverage Hours
- 5
- MarginOverage Target Margin
- 0.4
- MarginMonthly Capacity Hours
- 40
Remaining Capacity Hours
Remaining Capacity Hours
productive capacity − included − overage hours7 hours/monthResult7 hours/month
Reports hours/month from the entered project, capacity and ex-tax commercial assumptions. The engine retains full precision; presentation is bounded for readability.
Retainer Pricing Planner formulas →Inputs used by these formula steps
- Remaining Capacity HoursIncluded Hours
- 20
- Remaining Capacity HoursLoaded Cost Per Hour
- 55
- Remaining Capacity HoursMonthly Overhead
- 250
- Remaining Capacity HoursUtilisation
- 0.8
- Remaining Capacity HoursScope Buffer Rate
- 0.1
- Remaining Capacity HoursTarget Margin
- 0.35
- Remaining Capacity HoursOverage Hours
- 5
- Remaining Capacity HoursOverage Target Margin
- 0.4
- Remaining Capacity HoursMonthly Capacity Hours
- 40
Inputs used
- Included hours
- 20
- Loaded cost per hour
- 55
- Monthly overhead
- 250
- Productive utilisation
- 0.8
- Scope buffer
- 0.1
- Target margin
- 0.35
- Expected overage hours
- 5
- Overage target margin
- 0.4
- Monthly capacity hours
- 40
Open this calculator with preset values
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| Parameter | Meaning | Unit | Allowed values | Presence | Default |
|---|---|---|---|---|---|
| includedHours | Monthly delivery hours included in the retainer. | hours/month | 0 to 10000000 | Required | 20 |
| loadedCostPerHour | Internal delivery cost. | currency units/hour | 0 to 10000000 | Required | 55 |
| monthlyCapacityHours | Total monthly team capacity. | hours/month | 0 to 10000000 | Required | 40 |
| monthlyOverhead | Overhead assigned to the account. | currency units/month | 0 to 10000000 | Required | 250 |
| overageHours | Hours delivered beyond included scope. | hours/month | 0 to 10000000 | Required | 5 |
| overageTargetMargin | Margin retained on overage work. | proportion of overage price retained as contribution | 0 to 0.99 | Required | 0.4 |
| scopeBufferRate | Explicit protection for scope uncertainty. | proportion of delivery cost added as scope buffer | 0 to 0.99 | Required | 0.1 |
| targetMargin | Contribution retained from revenue. | proportion of client price retained as contribution | 0 to 0.99 | Required | 0.35 |
| utilisation | Share of monthly capacity available for delivery. | proportion of available retainer capacity billable | 0 to 0.99 | Required | 0.8 |
Retainer Pricing: monthly and annual fee
The retainer pricing result uses only the entered commercial assumptions.
Formula summary
- Primary formula
- monthly fee = buffered delivery cost ÷ (1 − target margin)
Data used here
- The estimate uses your inputs and the general business formula documented in the methodology.
Decision checks
Stress-test the decision
Retest utilisation, scope buffer, overage hours and remaining capacity before agreeing rollover or unlimited support.
When this estimate can be misleading
- Results depend on the accuracy and consistent basis of user-entered assumptions.
- The planner does not forecast demand, delivery performance or contract outcomes.
- Use the result as educational business decision support, not accounting, tax or legal advice.
- The retainer pricing result uses only the entered commercial assumptions.
Educational estimate, not advice. See all assumptions & limitations →
Related reading
Guides to interpret the decision and its assumptions.
- How to Build a Retainer Price From Capacity
Define the reserved-capacity promise, delivery boundary and review triggers before calculating a retainer fee.
Read guide
Frequently asked questions
How do I set a sustainable monthly retainer?
Set the retainer, overage rate and explicit included-scope and capacity boundaries.
Which planning assumptions should I stress-test?
Compare a plausible alternative scenario and verify the decision-critical assumption that changes the plan most.