Fairfax County

Fairfax County tightened its data-centre approval requirements in late April/early May 2026, adding 200-foot setbacks from residential properties, building-design controls, and mandatory noise studies for new data-centre applications. The changes were adopted in the same week that Loudoun County stripped data centres of by-right zoning and the Virginia Court of Appeals upheld a ruling blocking Prince William County's fast-tracked rezoning — a concurrent three-county tightening that reshaped the Northern Virginia consent environment.

Fairfax County is the most populous jurisdiction in Virginia and the second-largest county in the United States by population, with roughly 1.2 million residents. It contains major data-centre corridors along the Dulles Technology Corridor and in areas served by Dominion Energy's Northern Virginia transmission infrastructure. Alongside Loudoun County, it forms the core of the Northern Virginia data-centre cluster, which collectively hosts over 5 GW of operational capacity — the world's largest concentration of data-centre power.

The new Fairfax requirements stop short of Loudoun's decision to eliminate by-right zoning, but the combination of setback, design, and noise requirements adds meaningful pre-application cost and lengthens planning timelines. Combined with Loudoun's Phase 2 Standards, the two counties effectively end the era of streamlined administrative approvals that drove the cluster's growth, without formally closing the pipeline.