Preliminary notices — also known as “pre lien notices” or “notices to owner” or “NTOs” — are sent by construction project participants at the start of construction or supply work to provide other parties notice that they are working on the project. Most states require subcontractors and suppliers to provide the notice to key project stakeholders like the property owner, the general contractor, and the construction lender. The notice does not create any mechanics lien or bond claim rights, however, it’s possible for a party to lose their lien and security rights if a required notice is not sent. The notices must typically be sent by certified mail, certified mail return receipt requested, or by registered mail. Learn more about preliminary notices.