A mechanics lien is a legal claim against a property, filed by someone who supplied labor or materials that improved it and wasn't paid. It turns your unpaid invoice into a security interest in the real estate itself — the property can't easily be sold or refinanced until the debt is resolved, and in the worst case the lien can force a sale to pay you.
It is the single strongest payment tool contractors, subcontractors and suppliers have, which is exactly why the law wraps it in strict deadlines: miss the notice or recording window and the right evaporates, leaving you an unsecured creditor at the back of the line.
General education, not legal advice — lien law is state-specific and changes. For your state's exact windows, use the free deadline calculator; for anything contested, talk to a construction attorney.
Free 50-state deadline calculators, a free license-renewal lookup, and an agent that watches every date and drafts the notices — from $29/mo, 50% off for a year with FOUNDING50.
Free calculators → Start free trial →