Provide a few details about your project and receive competitive quotes from local pros. The average national cost to build a garage is $23,573, with most homeowners spending between $14,621 and $32,525.When it comes to building a garage, a lot of factors come into play, which mimic other large-scale building projects.rovide a few details about your project and receive competitive quotes from local pros. The average national cost to build a garage is $23,573, with most homeowners spending between $14,621 and $32,525.