Finance

What is budget variance in construction?

Budget variance is the difference between what a job or cost code was budgeted to cost and what it is actually costing or projected to cost. Positive means under budget; negative means over.

An office manager and contractor review invoices with a calculator and laptop in a construction office.
Review invoices, committed costs, and cash timing together before making project decisions. AI-generated illustration.

Budget variance compares the plan to reality. On a construction job it is calculated by cost code: the current budget minus the projected final cost (or minus actual cost to date, for a narrower view). A positive variance means the code is coming in under budget. A negative one means it is over. Some companies flip the sign, so make sure everyone reading the report knows the convention.

The useful version is the projected variance, because it includes what is left to spend. Actual-to-date variance alone can look fine right up to the month a job falls apart.

How to calculate budget variance

  • Current budget = original budget + approved change order budgets + approved budget transfers.
  • Projected final cost = actual cost to date + cost to complete.
  • Projected budget variance = current budget minus projected final cost.
  • Variance percent = projected variance divided by current budget.

Example: weekly variance review on a $1.4 million job

Example projected budget variance by cost code
Cost codeCurrent budgetActual to dateCost to completeProjected finalVariance
Sitework$148,000$151,200$0$151,200($3,200)
Concrete$212,000$176,500$28,000$204,500$7,500
Framing$186,000$121,000$82,000$203,000($17,000)
Electrical sub$164,000$71,000$93,000$164,000$0
General conditions$118,000$64,000$62,000$126,000($8,000)

Framing is the problem: $17,000 over, and two-thirds done by cost. The PM digs in and finds two causes. A crew lost three days to a late truss delivery, and the second floor layout changed by ASI after walls were already framed. The ASI work is a potential change order, and the truss delay may be backchargeable to the supplier. Without the variance report, both would likely have been forgotten by closeout.

General conditions is also over, which usually means the schedule is running long. That deserves its own look, since time overruns hit general conditions every week until they stop.

What causes budget variance

  • Estimating errors or missed scope.
  • Productivity below what the estimate assumed.
  • Price increases on materials since bid day.
  • Extra work done without an approved change order.
  • Miscoded costs, which create false variances on two codes at once.
  • Schedule delays that extend time-based costs.

Common mistakes

  1. Looking only at actual to date, without a fresh cost to complete.
  2. Not updating the budget for approved change orders, which makes healthy codes look over.
  3. Moving budget between codes to hide an overrun. Transfers should be approved and logged.
  4. Reviewing variance once a month. Weekly catches problems while there is still time to fix them.
  5. Explaining variances without assigning an action and an owner.

Related terms

See variance, estimate at completion, job cost report, and cost report. Read how to find margin fade on construction projects and use the construction budget template. Smart Business Automator shows budget, actual, and change orders by job and cost code, with risk alerts when costs drift. See job costing and WIP automation.

Frequently asked questions

Is a positive budget variance good?

In the common convention, budget minus cost, a positive variance means under budget, which is good. Some reports use the opposite sign, so check how your report is set up.

What is the difference between budget variance and cost variance?

They are often used interchangeably. In earned value management, cost variance specifically means earned value minus actual cost, which measures cost performance on the work done so far.

How often should budget variance be reviewed?

Weekly on active jobs is common for contractors who track margin closely. Monthly is the minimum, usually tied to WIP and billing.

Should change orders change the budget?

Yes. Approved change orders should add budget to the affected cost codes. Otherwise variances will be wrong.

Written and edited by

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

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