Estimating

What is contingency in construction?

Contingency is an amount carried in a construction budget or price to cover costs that are expected to show up but cannot be identified or priced yet, such as minor scope gaps, estimating misses, or unknown conditions.

Two construction professionals review paper plans beside a tablet at a jobsite workbench.
Plan reviews connect field conditions, drawings, and the next decisions on a job. AI-generated illustration.

Every estimate is wrong somewhere. Contingency is the money that absorbs it. It is not profit and it is not a slush fund. It is a budget line for real risk: the conduit run that is longer than the drawings show, the wall that turns out to have rot behind it, the sub that goes out of business halfway through.

Who holds the contingency, and who can spend it, depends on the contract. That question causes more arguments than the amount itself.

Types of contingency

Who holds the contingency
TypeHeld byUsually covers
Owner contingencyOwnerOwner changes, design errors, unforeseen conditions
Design contingencyEstimator or CM during designScope not yet drawn
Contractor or CM contingencyContractor, inside a GMPBuyout gaps, estimating misses, coordination issues
Bid contingencyContractor, inside a lump sumGeneral risk, rarely shown to the owner

On a lump-sum contract, the contractor's contingency is just part of the price, and whatever is unspent becomes profit. On a GMP contract, the CM contingency is a visible line, its use is usually reported to the owner, and unspent amounts are often shared or returned.

How contingency works on a real job

Say a CM has a $5.4 million GMP on a church renovation with a $162,000 CM contingency (3 percent of the cost of the work in this example). Three months in:

  • The drywall buyout came in $18,000 over the estimate. The CM moves $18,000 from contingency to drywall.
  • Demo uncovers abandoned ductwork the drawings did not show. Removal costs $9,400. The contract treats this as an unforeseen condition, so it comes from owner contingency, not CM contingency.
  • The owner asks for upgraded sanctuary lighting at $41,000. That is a scope change. It goes on a change order and increases the GMP; contingency is not touched.
  • Remaining CM contingency: $144,000. The CM reports the balance and each draw on it in the monthly report.

How much contingency to carry

There is no single right number. Contingency should match the risk: renovation and early-design estimates need more than a new building bid from finished drawings. Many estimators set it item by item using a risk register instead of one flat percentage. The guide on how to estimate construction contingency shows that method.

Common contingency mistakes and disputes

  1. Using contractor contingency to pay for owner-requested changes, which hides scope growth.
  2. Owners treating CM contingency as theirs to spend on upgrades.
  3. Burning contingency early on small items, leaving nothing for the expensive problems that come late in a job.
  4. No log of contingency use, so at closeout nobody can explain where it went.
  5. Showing contingency on a lump-sum bid and inviting the owner to negotiate it away.

Related terms

See allowance, escalation clause, concealed conditions, and guaranteed maximum price. Smart Business Automator's job costing view can carry contingency as its own cost code so every transfer is visible.

Frequently asked questions

Is contingency the same as an allowance?

No. An allowance is a set amount for a known item whose details are not chosen yet, like tile or light fixtures. Contingency covers unknown risks.

Who gets unused contingency?

It depends on the contract. On a lump sum, it stays with the contractor. On a GMP, unused CM contingency is often returned to the owner or shared under a savings clause.

Should contingency be shown on a bid?

On hard-bid lump-sum work, most contractors build it into the price rather than show it. On GMP and cost-plus work, it is usually a separate, visible line.

Can contingency pay for change orders?

Owner contingency often funds owner changes. Contractor contingency usually cannot be used for owner-requested scope; those should be change orders.

Written and edited by

Maurice Francois writes and edits construction operations guides for Smart Business Automator. More from Maurice on the Scaling Legends podcast.

Get a free assessment