Estimates are for planning purposes only and based on 2025 contractor data.
Always get at least 3 quotes before hiring. Prices vary by ZIP code, site conditions, and contractor availability.
12×20 deck costs between $4,800 and $15,600 for most homeowners in 2026, depending on material and location. At 240 square feet, it is a versatile mid-size deck that works well for both dining and lounging and fits homes where the yard is deeper than it is wide.
Frequently Asked Questions
How much does a 12×20 deck cost in 2026?
A 12×20 deck costs between $4,800 and $8,400 for pressure-treated wood and $8,400 to $15,600 for composite decking. Labor rates vary significantly by state, so use the calculator above for a location-specific estimate.
How does a 12×20 compare to a 12×16?
A 12×20 gives you 48 extra square feet compared to a 12×16. That extra length is enough to add a dedicated grilling area or a small lounge section alongside your dining furniture.
What can fit on a 12×20 deck?
A 12×20 deck can fit a 6-person dining table, a grill station, and a small loveseat or two lounge chairs. It is one of the most functional layouts for everyday outdoor use.
How long does it take to build a 12×20 deck?
Most contractors complete a 12×20 deck in 4 to 7 days. Elevated builds or designs with stairs and railings on multiple sides will take longer.
More Deck Size Calculators
Deck Cost by State
Ready to build your deck?
Get free quotes from local deck contractors - no obligation.
Get Free Quotes from Angi →