The average cost to build a garage is $65 per square foot. The cost to build a 1-car garage is between $12,500 to $24,200, a 2-car garage costs $19,600 and $28,200, and a 3-car garage ranges from $28,200 to $48,700. Depending on many factors, homeowners can expect to see about an 80% return on their investment in relation to home value.