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GENERAL CONTRACTOR

Construction Retainage Calculator

Retainage is a percentage the client holds back from each draw to protect against incomplete work. The risk is that it quietly ties up cash flow, so price it and plan for it before the contract is signed.

JOB INPUTS

Enter your numbers

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Total contract value

$
Total contract value

Percent the client holds back

%
Percent the client holds back

Share of the contract billed so far

%
Share of the contract billed so far

Release half when the job is substantially complete

Release half when the job is substantially complete
Results update automatically
CALCULATED RESULTUSD
Retainage currently held$12,500.00
Total retainage (project end)$25,000.00
Billed amount$250,000.00
Net received so far$237,500.00
FORMULA USED$250,000.00 × 10.0% = $25,000.00 → half released: $12,500.00

HOW TO USE IT

How to use the Construction Retainage Calculator

  1. 1

    Read the contract clause: Retainage rates differ by project and sector. Ten percent is common on commercial work, and many public and private clients hold it until substantial completion.

  2. 2

    Multiply the contract value: For a $250,000 contract at 10%, the total retainage is $25,000. The amount actually withheld rises with the billed portion, not the whole contract up front.

  3. 3

    Apply the release schedule: If the fully billed contract releases half at substantial completion, the amount still held falls to $12,500. The remaining half releases under the contract's final-acceptance terms.

  4. 4

    Plan cash flow around it: The retained balance is money you have already earned but cannot collect. Build it into your payment schedule and cover it with working capital or a clear drawdown plan. Use the Construction Retainage Calculator to see the numbers.

THE MATH

Retainage calculation method

Multiply the amount billed to date by the retainage percentage. On a fully billed $250,000 contract at 10%, $25,000 accrues; if the contract releases half at substantial completion, $12,500 remains held.

For a $250,000 contract at 10%, the total retainage is $25,000. The amount actually withheld rises with the billed portion, not the whole contract up front.

PRACTICAL EXAMPLE

Worked example for Retainage

Multiply the amount billed to date by the retainage percentage. On a fully billed $250,000 contract at 10%, $25,000 accrues; if the contract releases half at substantial completion, $12,500 remains held.

FAQ

Frequently asked questions

How do you calculate construction retainage?

Multiply the amount billed to date by the retainage percentage. On a fully billed $250,000 contract at 10%, $25,000 accrues; if the contract releases half at substantial completion, $12,500 remains held.

What should I verify before using the result?

Retainage is not a loss, but it is a timing cost. Plan the release milestones the same week you plan the draws.

Is this a final quote or design?

No. Use it as a planning estimate, then confirm measurements, local rates, product requirements, permits and jobsite conditions before bidding or building.