Mechanic's lien
A legal claim a contractor, subcontractor, or supplier can place on your home's title when they aren't paid for work or materials — even if you already paid your general contractor in full.
A mechanic's lien (also called a construction lien) is a security interest in your property's title that exists in every U.S. state to guarantee that anyone who supplied labor or materials gets paid. The trap for homeowners: a subcontractor or supplier can lien your home if your general contractor took your money but never paid them — meaning you can end up paying twice, and the lien can block a sale or refinance until it's cleared. Protect yourself by paying with a schedule tied to milestones, getting a [lien waiver](/glossary/lien-waiver) from the GC and every sub and supplier as you pay, and obtaining a final lien-release affidavit before the last payment. Our guide on [finding and vetting a good contractor](/guides/how-to-find-and-vet-a-contractor) walks through the paperwork. Lien laws and deadlines vary by state.