FMR Areas vs. ZIP Codes: How HUD Defines Geography

HUD's geographic framework for Fair Market Rents is based on metropolitan statistical areas and non-metropolitan counties — not individual ZIP codes. Understanding this framework helps make sense of why your specific neighborhood's rental market may not be perfectly captured by the published FMR for your area.

Metropolitan FMR Areas

For most metropolitan areas, HUD publishes a single FMR that applies across the entire metro, from the urban core to suburban and exurban areas within the MSA boundary. A Chicago resident pays the same FMR as someone in suburban DuPage County, even though rents differ substantially between those areas.

Non-Metropolitan Areas

Outside MSAs, FMRs are typically county-based. Each non-metropolitan county has its own FMR, allowing for better calibration to local rental markets in rural areas.

Small Area FMRs: The ZIP Exception

For designated high-cost metro areas, HUD publishes Small Area FMRs at the ZIP code level. This adds nuance to the metro-wide approach, better reflecting neighborhood-level variation.