Understanding AMI: Area Median Income Explained

Area Median Income — often abbreviated AMI — is one of the most important numbers in affordable housing policy. It's the foundation for income limits, LIHTC rents, Section 8 eligibility, and dozens of other programs. Yet many people who are affected by it every day have never heard of it.

What AMI Is

AMI is simply the midpoint household income in a given geographic area — the income level where half of all households earn more and half earn less. HUD calculates it separately for each metropolitan area and non-metropolitan county, reflecting the significant variation in income levels across the country. The AMI for a 4-person household in San Francisco is over $150,000; in rural West Virginia it's around $52,000.

Why Household Size Matters

AMI figures are anchored to a 4-person household, but HUD adjusts the limits up or down based on actual household size. A 1-person household has a lower income limit than a 4-person household; an 8-person household has a higher one. This prevents smaller households from being excluded even though their total income may be the same as a larger household's.

The Key AMI Thresholds

• 30% AMI — Extremely Low Income. Priority status for most federal housing programs. A 4-person household in most US metros earns under $25,000 at this level.
• 50% AMI — Very Low Income. The primary Section 8 voucher eligibility ceiling.
• 60% AMI — Key LIHTC threshold for maximum gross rents.
• 80% AMI — Low Income. Eligible for HOME program and many other assisted housing programs.

Check income limits for your area to see current AMI thresholds.