Deck cost per square foot in 2026 - and what a deck quote must include

Two contractors quote the same 16 by 20 deck. One says $14,000, the other says $23,500. Neither is cheating you. They are quoting different jobs, and the difference is almost never the decking boards.

Deck cost per square foot in 2026

Installed, including framing, fasteners and labour. A 320 square foot deck is the reference size.

Composite costs more up front and nothing to maintain. Pressure-treated costs less and wants cleaning and sealing every other year. Over twenty years the two land closer together than the sticker suggests.

What actually moves the price

In rough order of impact, and none of these are the boards:

• Height off the ground. A ground-level deck needs no railing and shallow footings. A second-storey deck needs posts, beams, railing, stairs and inspection. Same square footage, half again the cost.
• Framing, new or reused. Re-decking a sound frame is a fraction of building one. A quote that assumes reuse is not comparable to one that prices new joists.
• Footings. Count and depth are set by frost line and soil. In the north that is 42 inches of hole per footing.
• Railing. Cable and glass systems can add $70-$150 per linear foot. On a 60 foot perimeter that is a five-figure decision by itself.
• Stairs. Expensive per step - framing, treads, railing on both sides, and a landing.
• Tear-off. Removing and disposing of an old deck typically runs $700-$2,000.

What a deck quote must include

If a quote is one line and one number, you cannot compare it to anything. Ask for these, in writing:

• Square footage, deck height, and whether it attaches to the house or stands free
• Framing specification: joist size, spacing, and whether the frame is new or reused
• Footing count, diameter and depth
• Decking material, brand and product line - not just the word composite
• Fastener type: hidden clips or face screws
• Railing type and linear footage; stairs and the number of steps
• Permit: who pulls it, and whether the fee is in the price
• Tear-off and disposal of the existing deck
• Warranty, split between material and workmanship, with years on both
• Payment schedule, with a deposit under a third of the total

How many deck quotes to get

Three. One tells you nothing, two makes the cheaper one look right, and beyond three you are running a procurement process for a deck. Get them within the same couple of weeks, since lumber pricing moves.

Red flags in a deck quote

• A deposit above a third of the total, or a demand for cash
• No permit line at all on a raised or attached deck
• No mention of footing depth in a frost-line state
• Composite decking over a frame the quote never describes
• A price that expires today. Real contractors have a backlog, not a countdown

Getting a number before anybody visits

You can size the job yourself. A deck footprint is easy to measure from aerial imagery, and multiplying square footage by the per-foot ranges above gets you within a sensible band. That number is not a quote - it is the thing that tells you whether the quotes you receive are reasonable.

Common questions

How much does a deck cost per square foot?

$30-$45 installed for pressure-treated, $45-$70 for composite, $60-$100 for hardwood. Raised decks sit at the top of each range.

Why are my deck quotes thousands of dollars apart?

Framing and footings, nearly every time. Compare the framing line before you compare the totals.

What should a deck quote include?

Size and height, framing spec, decking brand, railing, footings, permit, tear-off and a split warranty.

Do I need a permit to build a deck?

Usually, once it is attached to the house or more than roughly 30 inches up. The contractor normally pulls it - confirm who pays the fee.