Iowa mechanics lien law is particularly unique as the filing process is done through the Iowa State Mechanic's Notice and Lien Registry. Any potential claimant will need to first register an account with the online registry.
Stying with the theme of unique lien laws, there are also multiple deadlines for filing a claim in Iowa as well.
For full protection of your lien rights, an Iowa mechanics lien must be posted to the registry within 90 days of last furnishing labor or materials to the project. Not only does this result in full protection of lien rights, but once posted, the registry administrator will send a copy of the lien as notice to the property owner.
If this deadline is missed, lien rights are still intact. Legally speaking, an Iowa lien can be filed up to 2 years after the 90 day period expires (i.e. 2 years + 90 days after last furnishing). However, if filed after the initial 90 day period, two things happen:
The claim will be limited to the "unpaid balance" due to the general contractor at the time the lien was posted; &
Written notice must be served by the claimant to the owner by certified mail with return receipt requested.