Established in 1975, Oregon's Special Assessment of Historic Property Program was the nation's first state-level historic preservation tax incentive.  It "freezes" a property's assessed value for 10 years.  It is most effective when the "freeze" is in place prior to any substantial rehabilitation of the property.
 
Basic program requirements are as follows:

• The property must be listed in the National Register of Historic Places, either individually or as a contributing property in a historic district, or be considered historic by the State Historic Preservation Officer, and listed within two years of being certified for the benefit program.
• A preservation plan must be prepared that outlines substantial rehab work the building will undergo during the 10-year period, with emphasis on exterior rehabilitation of the structure.
• There is an application fee equal to 1/10 of 1% (0.001) of the assessed value.
• 10% of the total real market value (RMV) of the property must be invested in rehabilitation within the first five years of the program. For most properties, this includes the RMV of both the building (improvements) and the land.
• State Historic Preservation Office (SHPO) approval or local government approval, whichever is appropriate, is needed for exterior projects, and interior projects of substance.
• An approved plaque provided by the Oregon SHPO must be installed on the building.

For more information please contact:
Oregon Parks & Recreation Department: Oregon Heritage: State Historic Preservation Office – http://www.oregon.gov/oprd/HCD/SHPO/Pages/tax_assessment.aspx