What it costs to stain a deck
The price follows the square footage. This is the deck floor only, one coat of semi-transparent stain, at our October 2026 prices:
| Deck size | Sq ft | Gallons | Stain only | Washed and stained by a pro |
|---|---|---|---|---|
| 10 × 10 ft | 100 | 1 | $35 | $185–$255 |
| 12 × 12 ft | 144 | 1 | $35 | $255–$345 |
| 12 × 16 ft | 192 | 1 | $35 | $330–$450 |
| 16 × 20 ft | 320 | 2 | $70 | $565–$760 |
| 20 × 20 ft | 400 | 2 | $70 | $690–$930 |
"Stain only" is the store bill if you do it yourself. The last column adds a painter at $1.50 a square foot and a wash at $0.35.
Don't forget the railing
The floor is the easy part. A railing is a few hundred narrow surfaces, and every one of them gets a brush. Tick the railing box and watch the square footage jump. On a small deck the railing can be as much work as the boards.
That's also why quotes for the same deck vary so much. Ask each painter whether the railing, the stairs and the outside of the rim are included.
Working out the gallons
Width times depth gives the floor. We count a railing as 6 square feet for every foot of length, which covers both faces of a 36-inch rail. Then divide by coverage: 250 square feet a gallon for semi-transparent stain and 200 for solid, less 25% on weathered wood.
The can in your hand has its own coverage number. Trust that one over ours.
Prep is most of the job
Stain only sticks to clean, dry, bare wood. A deck that has gone gray needs a deck cleaner or a gentle pressure wash, then a day or two of dry weather. If the old finish is peeling, it has to come off first, and stripping costs more than staining.
New pressure-treated boards need to dry out before they'll take stain. Sprinkle water on them: if it beads, wait.
Picking the day
Stain in mild, dry weather and out of direct midday sun. On hot boards the stain dries before it soaks in, and it shows as lap marks. Check that no rain is due for a day or two afterward.
Fair questions
How often does a deck need restaining?
Every two to three years is the usual guideline, and a deck in full sun needs it sooner than a shaded one. The test is the same as for a fence: when water soaks into the boards instead of beading, it's time.
Is a deck harder on stain than a fence?
Yes. A deck lies flat, so water and snow sit on it and people walk on it. That's why decks are restained more often than fences.
Does composite decking need stain?
No, which is most of its appeal. The composite vs wood calculator shows what that saves over the years.
Sources
- How we calculate: every suggested price behind this calculator, with the date it was last reviewed.
