California Set 2027 Historical Property Interest Rate
The state board established a 6.75 percent interest component for valuing historical property assessments.
Updated on Oct. 5, 2026 in Commercial
The California State Board of Equalization has set the historical property interest component for the 2027 assessment year at 6.75 percent. This figure is derived from the Federal Home Loan Mortgage Corporation effective average mortgage interest rate.
Why it matters
State law requires this annual interest component determination to guide how county assessors calculate property values. It ensures that historical properties are assessed using a consistent capitalization of income method across the state.
The California State Board of Equalization set the 2027 historical property interest component at 6.75 percent, reflecting the rounded Federal Home Loan Mortgage Corporation effective average mortgage rate of 6.71 percent as of September 1.
The players
California State Board of Equalization
This is a California state agency tasked with administration of tax laws and the equalization of property assessment values.
Federal Home Loan Mortgage Corporation
Also known as Freddie Mac, this public government-sponsored enterprise supports the liquidity and stability of the mortgage market.
The details
County assessors utilize a capitalization of income method to determine the value of historical properties, which relies on this statutorily required interest component. Revenue and Taxation Code sections 439 through 439.4 mandate this annual calculation.
Timeline
September 1, 2026: Mortgage interest rate benchmark measurement date.
2027: The assessment year for the newly established interest component.
Culture Shift
The adjustment follows the regulatory framework established by Revenue and Taxation Code sections 439 through 439.4, which dictates how California manages historical site valuations. This process ensures that property tax assessments remain anchored to current national mortgage trends.
Owners of designated historical properties in California will see their annual assessment values calculated using this 6.75 percent interest rate. This metric directly influences how the capitalization of income method is applied to their property taxes.
The takeaway
Property owners should anticipate that the 6.75 percent component will influence upcoming tax valuations for eligible historical structures. Staying informed on these annual interest adjustments allows for better long-term financial planning regarding property upkeep and tax liabilities.
Further reading
For more on state business regulations, visit California Commercial.
