How to find out if a contractor is licensed.

All states that license contractors and tradesmen keep lists of license holders. Click on the abbreviation for your state in the map to see the phone number (and usually a Web address) for your state licensing board. A phone call or several mouse clicks will identify exactly who is licensed and who isn’t.

Except for plumbers and electricians, tradesmen paid by the hour usually don't need a license. Contractors bidding on any significant work (more than a few hundred dollars) need a license in most states. If you have a problem with a licensed contractor or tradesman, the state licensing board can be a powerful ally in resolving issues. Get into a dispute with an unlicensed contractor or tradesman and you’re on your own.

All construction contractors need liability and workers’ compensation coverage. Request a certificate of insurance from the contractor you select. Insurance carriers provide certificates showing policy limits and coverage dates. There's usually no charge for these certificates.