Permit may or may not be required, it depends on local building code. Be sure to call your city or county building department.
For instance, for residents in Los Angeles County, it is required that you have a building permit to construct a carport structure. In order to obtain a building permit you will need a site plan of the proposed carport showing its size and setbacks from property lines. A building permit fee is based on the valuation of the structure plus a nominal permit issuance fee. A licensed contractor is recommended for any construction project, but a homeowner/builder can take responsibility for construction regardless of who actually performs the work. You or your contractor may obtain the required permit(s) at the District Office serving your area, a link is provided for your convenience for locations of our district offices.
Make sure to call your city or county building departments and ask them if you will need one.