Retainage Calculator
Calculate retainage step by step: Earned = contract × % complete.
How do I calculate retainage on a construction payment?
Multiply the value of work completed by the retainage rate to get the amount held back, then subtract retainage and previous payments from earned value to get the payment due.
Formula: Earned = contract × % complete. Retainage = earned × rate. Due = earned − retainage − previous payments.
How retainage is calculated on a progress payment
Earned to date = contract value x percent complete. Retainage held = earned to date x retainage rate. Payment due = earned to date - retainage held - previous payments.
Retainage on a 200,000 contract at 10%
| Percent complete | Earned to date | Retainage held | Paid before retainage release |
|---|---|---|---|
| 25% | 50,000 | 5,000 | 45,000 |
| 50% | 100,000 | 10,000 | 90,000 |
| 75% | 150,000 | 15,000 | 135,000 |
| 100% | 200,000 | 20,000 | 180,000 |
Where the retainage rate comes from
The rate is set by your contract and, on many public projects, by state or federal law. Some contracts reduce or stop retainage once a project passes a stated milestone. Enter the rate your contract states; the calculator does not apply any jurisdiction's rules.
Retainage release at completion
When the contract's completion conditions are met, the held amount is released. At 100% complete the total retainage equals the contract value x the retainage rate.
What this calculator does
Calculate retainage step by step: Earned = contract × % complete. Worked example, questions and limitations included.
You enter currency, contract value, work completed to date and retainage rate and a few other details, and the retainage calculator shows the answer along with the working, so you can check it or try other numbers.
The page shows the formula, a numeric worked example, and the assumptions that affect this construction calculation.
Inputs and what they mean
- Currency
- — choice value.
- Contract value
- — number value.
- Work completed to date
- — number value.
- Retainage rate
- — number value.
- Previous payments made
- — number value.
How to use it
- Enter each value in the unit shown next to the box (use the unit converter first if your numbers are in other units).
- Check the breakdown to see every intermediate step.
- Read the limitations before relying on the result.
Formula
Retainage is released on completion per the contract.
Rate is entered — laws and contracts set different limits.
A negative result means overpayment to date.
Earned = contract × % complete. Retainage = earned × rate. Due = earned − retainage − previous payments.
Inputs used: Currency, Contract value, Work completed to date, Retainage rate, Previous payments made.
Worked examples
Worked example: 50% complete, 10% retainage, 40,000 already paid
- Earned = 200,000 x 50% = 100,000
- Retainage = 100,000 x 10% = 10,000
- Due = 100,000 - 10,000 - 40,000 = 50,000
Reading the result
The headline figure is the main answer. Any breakdown underneath shows the parts that make it up, so you can check the working and see what changes when you adjust an input.
Reference price tables
No reference prices are configured. Enter your own prices and rates — this site never assumes them.
Limitations and assumptions
- Single retainage rate.
- No stored materials or change orders unless included in contract value.
- Local law may change the rules.
- Results are estimates for planning and learning. Real designs, installations and bids must be checked by a qualified, licensed professional against the codes that apply where you work.
- The result depends on the values you enter for this retainage calculator; it does not supply missing rates, rules, prices, dates, or assumptions for you.
Reference: OpenStax (Rice University)
Last reviewed:
Common questions
How do I calculate retainage on a construction payment?
Multiply the value of work completed by the retainage rate to get the amount held back, then subtract retainage and previous payments from earned value to get the payment due.
What is retainage?
A percentage of each progress payment the owner holds back until the work is complete, as security for defects and completion.
Is there a legal limit?
Many jurisdictions cap retainage or require release after substantial completion. Check local law and your contract.
Can retainage reduce over time?
Some contracts reduce the rate after a milestone, such as 50% completion. Run the calculator with the new rate for later periods.
What does retainage mean in construction?
Retainage (or retention) is a percentage of each progress payment the owner holds back until the work is complete. The rate comes from your contract and local law; the calculator uses the rate you enter.
How do I use the Retainage Calculator?
Enter the required values for Currency, Contract value, Work completed to date, Retainage rate, Previous payments made. The calculator applies the formula on this page and shows the main result with any supporting breakdown so you can check the arithmetic.
Sources
Method based on OpenStax (Rice University).
Cite this page
Free Calculator. (2026, November 3). Retainage Calculator. https://freecalculator.tech/tools/retainage-calculator
"Retainage Calculator." Free Calculator, 3 Nov. 2026, https://freecalculator.tech/tools/retainage-calculator.
Retainage Calculator — Free Calculator, https://freecalculator.tech/tools/retainage-calculator
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