A conditional lien waiver releases the contractor's or supplier's lien rights for a specific amount or period, but only on the condition that the payment actually clears. If the check bounces or the wire never lands, the waiver is void and lien rights are preserved. Conditional waivers are the right tool for waivers exchanged simultaneously with payment delivery.
Most states publish or recognize statutory forms for both conditional and unconditional waivers, separately for progress payments and final payments. California, Texas, and Florida each have specific required language that must be used to be effective. Always use a conditional waiver when accepting a check at a payment-exchange meeting; switch to unconditional only after the funds have cleared the bank.