State Preemption of Local Zoning in Oregon

What Is State Preemption?

State preemption occurs when a state law overrides local government ordinances in a specific area. In land use, preemption means a city or county cannot adopt zoning rules that are more restrictive than the state standard. If a city tries to prohibit something the state law permits, the state law wins.

Oregon actively uses preemption in housing law. The state has enacted legislation that prohibits local governments from blocking certain types of housing development — most notably accessory dwelling units (ADUs) and lot splits.

Compare all 51 jurisdictions: ADU preemption table · Short-term rental preemption table

ADU Preemption

What local governments cannot restrict:

• ✓Eliminates single-family-only zoning in Oregon cities with population 10,000 or more — duplexes must be allowed by-right in single family residential zones · Source
• ✓Local jurisdictions must adopt compliant code or be subject to state model code · Source

Lot Split Preemption

Oregon Senate Bill 458 (SB 458) — Middle Housing Lot Division (effective 2022-07-01)

How Preemption Affects Oregon Cities

State preemption applies to every incorporated city and unincorporated area in Oregon. Select a city below to see how state preemption interacts with local zoning rules.