Pricing
How to estimate a paint job by the square foot
Quick answer
Measure net wall area (perimeter × height minus big openings), then build your rate: labor and overhead per hour divided by the square feet you paint per hour, plus paint cost per square foot, divided by one minus your margin. Price prep as a separate line.
Customers love a price per square foot because it feels simple and easy to compare. Painters love it less, because the same square foot of wall can take five minutes or twenty depending on what is on it. Both can be true at the same time. A price per square foot works well, as long as it comes from your own costs and the prep is priced separately.
This guide shows how to measure a room, how to build your own rate per square foot from your real costs, and where the method breaks down.
Step 1: measure the walls
For a rectangular room, the wall area is the perimeter times the height, minus the big openings.
Let's take a bedroom that is 12 by 14 feet with 8-foot ceilings, one door and two windows:
| Measurement | Calculation | Result |
|---|---|---|
| Perimeter | 2 × (12 + 14) | 52 ft |
| Gross wall area | 52 ft × 8 ft | 416 sq ft |
| Door | 3 ft × 7 ft | − 21 sq ft |
| Two windows | 2 × (3 ft × 4 ft) | − 24 sq ft |
| Net wall area | 416 − 21 − 24 | 371 sq ft |
Only subtract large openings. Small ones take nearly as long to cut around as the wall they replace, so leaving them in is a fair way to cover that time.
Step 2: measure ceilings and trim separately
Ceilings are length times width: 12 × 14 = 168 sq ft for the same room. Price them separately, because ceiling work is slower and customers do not always want it.
Trim is measured in linear feet. For baseboards, a quick estimate is the perimeter minus the door openings: 52 − 3 = 49 linear feet. Doors and window frames are usually easier to count and price per piece.
Keeping walls, ceilings and trim on separate lines lets the customer add or remove items without you rebuilding the whole bid.
Step 3: build your rate per square foot from your costs
A rate per square foot is just your costs, divided by how much you paint in an hour, plus your margin. You need four numbers:
- Your production rate: square feet of wall your crew finishes per hour, with the number of coats you normally apply and the cutting in. Time your own crew; do not borrow someone else's number.
- Your real labor cost per hour: wage plus payroll costs. The complete pricing guide explains how to work it out.
- Overhead per billable hour: your monthly fixed costs divided by the hours you actually invoice.
- Paint cost per square foot: the price of a gallon divided by the coverage printed on the label, times the number of coats.
Say your crew paints 100 square feet of wall per hour with two coats, your real labor cost is $31.43 an hour, your overhead is $20 per billable hour, and you use a paint that costs $40 a gallon with a label coverage of 350 square feet per gallon. These are example numbers to show the math:
| Cost per square foot | Calculation | Amount |
|---|---|---|
| Labor | $31.43 ÷ 100 sq ft | $0.314 |
| Overhead | $20 ÷ 100 sq ft | $0.200 |
| Paint, two coats | ($40 ÷ 350) × 2 | $0.229 |
| Cost per sq ft | $0.743 | |
| Price per sq ft at 20 % margin | $0.743 ÷ 0.80 | $0.93 |
That $0.93 is a rate for walls in normal condition, two coats, same color family. It is yours, because it comes from your crew's speed and your costs. The division by 0.80 keeps 20 percent of the price as profit; markup vs margin explains why adding 20 percent to cost would leave you short.
Step 4: price the prep as its own line
Moving furniture, covering floors, filling holes, sanding, spot priming and masking do not scale with square feet. A small room full of furniture can take longer to prepare than a large empty one.
Estimate prep in hours and price it with the same hourly cost and overhead. For our bedroom, say 1.5 hours of prep and protection:
- Cost: 1.5 h × ($31.43 + $20) = $77.15
- Price at 20 % margin: $77.15 ÷ 0.80 = $96.43
Step 5: add it up for the room
| Line | Calculation | Price |
|---|---|---|
| Walls, two coats | 371 sq ft × $0.929 | $344.51 |
| Prep and protection | 1.5 h | $96.43 |
| Walls total | $440.94 |
Ceilings and trim go on top, each priced with their own production rate. Round the total up to a clean figure for the bid.
One detail on materials: the walls need 742 square feet of coverage (371 × 2 coats), which is a little over two gallons at 350 square feet per gallon. You will buy three. Either price the full gallons or leave the extra paint with the customer for touch-ups and say so in the bid.
How to keep your rate honest
- Recalculate it whenever wages, overhead or paint prices change.
- Keep separate rates for walls, ceilings and exteriors; they are different work.
- After each job, compare the hours you estimated with the hours it took. If you are always over, your production rate is too optimistic.
What to do next
Use this method to measure, then follow how to price and bid a paint job to turn the numbers into a written bid the customer can accept. For quick checks on any job, the job price calculator works from hours, materials and margin.
Frequently asked questions
Should I subtract windows and doors from the wall area?
Subtract large openings like doors and big windows. Leave small ones in, because cutting around them takes about as long as painting the wall they replace.
Is one price per square foot enough for every job?
No. Keep separate rates for walls, ceilings and exteriors, and price prep, repairs and difficult access as separate lines.
Where do I get the paint coverage number?
From the label or technical data sheet of the product you use. It changes between products and between smooth and textured surfaces.