A paint estimate is five numbers added together: paint and materials, labor, prep, overhead, and profit. Get those right and the price almost builds itself. Guess at any one of them and you either lose the job or lose money winning it.
- Measure surfaces, not rooms
- Paint by coverage and coats
- Labor by your production rate
- Add overhead and profit, always
Estimating is the part of painting that decides whether the job is worth doing, and it's the part most shops do by feel. A good estimate isn't a lucky guess at a round number. It's a short calculation you can defend, repeat, and hand to a customer as a clean proposal. This guide walks the whole thing, start to finish, with a worked example you can copy.
The estimate formula
Every paint estimate, interior or exterior, is the same five pieces:
Paint + labor + prep + overhead + profit = the price.
Skip overhead and profit and you've priced a hobby, not a business. The first three cover what the job costs you. The last two are why you're in business at all. Everything below is just how to fill in each number.
Step 1: Measure the surfaces
You don't price rooms, you price surfaces. Walls, ceilings, trim and doors each paint at a different speed and take different amounts of product, so they get measured separately.
- Walls: add up the wall lengths to get the perimeter, then multiply by the ceiling height. A 12 by 14 room with 9 foot walls is (12+14) × 2 × 9 = 468 square feet.
- Ceilings: length times width. That same room is 12 × 14 = 168 square feet.
- Trim, doors and windows: count them, or measure trim by the linear foot. These are priced per unit or per foot, not by wall area.
You can subtract big openings like garage doors and picture windows, but most painters skip small deductions. The few square feet you'd save aren't worth the math, and they buffer the cut-in time around them.
Step 2: Figure paint and materials
Paint coverage is printed on every can, and it's usually around 350 square feet per gallon for a smooth surface. Rough or porous surfaces drink more. The math is simple:
surface area ÷ coverage × coats = gallons
So 468 square feet of wall at 350 per gallon, two coats, is 468 ÷ 350 × 2 = about 2.7 gallons, which you round up to 3. Always round up. Running out mid-wall costs more than a spare quart.
Then add sundries: tape, plastic, paper, roller covers, brushes, caulk, filler. A flat materials add-on per job, or a small percentage, keeps you from nickel-and-diming every roll of tape into the estimate.
Dark-to-light, bold colors and bare drywall almost always need an extra coat or a primer. An estimate built on two coats that actually takes three is the single fastest way to paint a job for free. Walk the space and decide coats per surface before you price anything.
Step 3: Price the labor
Labor is where estimates go wrong, because it's the one number you can't read off a can. The fix is a production rate: how much area your crew covers in an hour. Track it on a few jobs and you'll never guess again. Example rates to start from and then replace with your own:
| Task | Example production rate |
|---|---|
| Rolling walls, per coat | ~180 sq ft / hour |
| Cutting in | ~70 linear ft / hour |
| Ceilings, per coat | ~200 sq ft / hour |
| Trim & doors | ~1 to 2 units / hour |
Illustrative starting points, not industry standards. Your real rates depend on your crew, the surfaces and the prep. Track a few jobs and use your own.
Take the surface area, divide by the production rate, multiply by coats, and you have hours. Multiply hours by your loaded labor rate, the one that covers wages, payroll taxes, insurance and worker overhead, not just take-home pay. That loaded rate is also the honest answer to "how much do painters charge per hour": it's higher than a wage because it has to be.
Step 4: Add prep, overhead and profit
Three things separate a number that looks like a deal from one that keeps the lights on.
Prep is its own line, never folded into "painting." Scraping, sanding, patching, caulking and masking can be half the labor on an older exterior. Estimate it as hours, the same way you do painting.
Overhead is everything you pay whether or not you're on a ladder: the truck, the phone, insurance, software, fuel, the time spent estimating. It gets spread across your jobs as a percentage. If you don't add it, your customers aren't paying for it, you are.
Profit is the markup on top of all of it. It's not a dirty word, it's the reason to take the risk of running a shop. Decide your target margin and apply it to every bid, not just the ones you feel good about.
People often ask the cost per square foot. It's a useful gut check, interior repaints commonly land somewhere around $2 to $6 per square foot of wall area once everything is in, but it's an output of this math, not a shortcut around it. Price the parts, then check the per-foot number against your market.
A worked example
Here's the whole thing on one small job. This also happens to be what a clean "painting estimate example" looks like before it becomes a proposal.
Every figure here is illustrative. Drop in your own paint cost, production rate, loaded labor rate and margin, and the same five steps give you a number you can stand behind.
Step 5: Turn it into a proposal
A number on its own invites haggling. The same number inside a clear proposal gets signed. Carry the estimate into a document that shows the scope and surfaces, the colors and sheens, what's included and what isn't, the total, and the terms. Offer a good, better and best option and the bigger package sells itself.
Skip the spreadsheet math.
BrushBid prices the job by the square foot and turns it into a signed proposal in minutes. Start free, no card.
Common estimating mistakes
- Pricing two coats, painting three. Decide coats per surface before you bid, not on the ladder.
- Burying prep in "painting." It's the line most likely to blow up. Give it hours of its own.
- Forgetting overhead. If the truck, phone and insurance aren't in the number, you're paying for the job.
- Copying someone else's hourly. Your loaded rate comes from your costs, not a forum post.
- Bidding slow. The fastest clean estimate usually wins. A week-late quote loses to a same-day one.