Concrete slab cost in Washington

If you are planning more than one job in Washington

Each project weights the trades differently, so Washington's wage level does not push every price by the same amount. Compared with the US midpoint, concrete driveway is +22% and detached garage +15%.

Wages behind the Washington number

Washington's labor line is priced from 4 trades, each compared with its US median wage. After weighting by each trade's share of the work, the state comes out at 1.31 times the national level.

Cement masons and concrete finishers (47-2051), 50% of the weighting: a median of $37.27 an hour, 36% above the US median of $27.41. The middle half of them earn between $28.31 and $47.25 an hour. About 4,440 work in the state. That is 12.5 per 10,000 jobs, compared with 13.3 nationally, so the supply of crews looks typical.

For construction laborers (47-2061, weighted 30%) the local median is $27.75 an hour, which is 22% above the national $22.66. The middle half of them earn between $22.56 and $34.69 an hour. BLS counts 25,060 of them working in the state, 70.6 for every 10,000 jobs (US: 70.5), so the local bench is about average.

Operating engineers and other construction equipment operators (47-2073), 10% of the weighting: a median of $39.28 an hour, 36% above the US median of $28.78. The middle half of them earn between $30.96 and $55.12 an hour. About 10,290 work in the state. That is 29.0 per 10,000 jobs, compared with 30.7 nationally, so the supply of crews looks typical.

Carpenters (47-2031), 10% of the weighting: a median of $35.67 an hour, 22% above the US median of $29.12. The middle half of them earn between $29.15 and $44.55 an hour. About 26,960 work in the state. That is 75.9 per 10,000 jobs, compared with 43.1 nationally, which suggests plenty of local crews to bid.

A crew paid at the 75th percentile for cement masons and concrete finishers ($47.25 an hour) would add about $290 to the statewide midpoint; one at the 25th percentile ($28.31) would take off about $260. Use that as a rough guide to how far a bid can sit from our midpoint on wages alone.

BLS counts 3,550,970 jobs across Washington (May 2025), which is 2.3% of US employment.

Extras that change the Washington total

Add-ons start from national price ranges and are scaled by 1.17 for Washington, which is the average of the area's wage index (1.31) and goods price index (1.04). The estimator above can add them to your total.

Weather windows across Washington

Weather decides when pouring concrete can happen, and Washington is not uniform. The table uses NOAA's 1991-2020 climate normals from the weather station nearest each metro we cover, and counts the months that are neither cold nor hot enough to complicate the job.

Seattle has the longest comfortable season of the metros we cover in Washington at 8 months (April through November); Kennewick has the shortest at 3 (May through June and September). Rainfall runs from 8 inches a year in Kennewick to 57 inches in Bremerton.

We do not adjust prices by month, because we have no reliable published data on seasonal pricing. Timing is still worth raising when you collect bids.

Washington against its neighbors

Washington ranks 4 of 51 (the 50 states plus DC) for concrete slab, where 1 is the most expensive. The costliest is Hawaii at $5,150 and the cheapest Arkansas at $3,350, both for 400 sq ft at the midpoint. Washington sits at $4,400. The five states closest by workforce center are listed below.

Which Washington city is cheapest for concrete slab?

2 of the 7 metros sit above the statewide midpoint of $4,400, and the top-to-bottom gap is 6%. Each row prices the default size with that metro's own BLS wages and BEA price levels, so the gap between rows is real local variation rather than a flat markup.

Basic, standard or premium: Washington prices

Bands overlap on purpose, since a good standard job can cost as much as a light premium one. Below are the three bands for the default size, then a grid from 10x10 pad (100 sq ft) to 30x40 foundation (1,200 sq ft).

Why two Washington quotes can differ

• Thickness and mix

  A 4-inch slab uses about 1.23 cubic yards of concrete per 100 sq ft; a 6-inch slab uses about 1.85. Stepping up from a 3,000 PSI to a 4,000-4,500 PSI mix adds $10-$40 per cubic yard (Estimators.us).

• Base and reinforcement

  A compacted gravel base, vapor barrier, and wire mesh or rebar are priced separately by some contractors and bundled by others. Ask which one your quote does.

• Truck and pump access

  If the mixer truck can't back up to the forms, someone has to wheelbarrow it in or hire a pump. Pump or line-pump hire is typically billed per day.

• Small-job minimums

  Many crews have a minimum charge, so a 10x10 pad can cost more per square foot than a 20x20 slab.

• Finish

  A broom finish is the baseline. Stamped, stained, or exposed-aggregate finishes are priced as add-ons on top of the slab.