Mechanics lien
A mechanics lien (also called a construction lien) is a legal claim against a property, filed by someone who worked on it or supplied materials for it and wasn't paid.
Updated October 13, 2026 · 1 min read
Who can file one
It depends on the state. California's statute, for example, gives lien rights to anyone who provides authorized work on a project, including direct contractors, subcontractors, material suppliers, equipment lessors, laborers and design professionals.
Deadlines and notices
Lien rights come with strict, state-specific steps. Many states require an early notice before anyone can file. In Florida, most lienors must serve a notice to owner before or within 45 days of starting, and missing it is a complete defense against the lien. Miss a deadline and the right can be gone.
Where waivers come in
Because a lien attaches to the property, an owner who paid the general contractor can still face a lien from an unpaid sub. Lien waivers are how owners collect proof that each payment reached the people who earned it.
Questions? Answers.
How can an owner avoid a surprise lien?
Collect lien waivers as money moves down the chain: a conditional waiver with each payment request and an unconditional one once it clears. Pay attention to any notices from subs or suppliers, which tell you who else is on the job.
Sources
- California Civil Code § 8400, who has a right to a lien · leginfo.legislature.ca.gov
- Florida Statutes § 713.06, notice to owner · leg.state.fl.us