Explainer
How HUD income limits work
A plain-English walkthrough of the 30%, 50%, and 80% Area Median Income thresholds — and the household-size adjustments that decide who actually qualifies.
The three tiers
HUD publishes income limits each year at three standard tiers, all expressed as a percentage of the Area Median Income (AMI) for a given county or metropolitan area:
- 30% AMI — Extremely Low Income. The deepest-need tier. Federal rules require that at least 75% of new Housing Choice Vouchers go to households below this threshold.
- 50% AMI — Very Low Income. The standard income cap for Section 8 voucher eligibility in most areas.
- 80% AMI — Low Income. The cap for project-based public housing and many other HUD programs, including some rural-development rental assistance.
Where the AMI number comes from
HUD calculates each county's "median family income" using American Community Survey data from the U.S. Census Bureau, with smoothing and inflation adjustments. The figure is then scaled to a 4-person household as the base, and household-size adjustments are applied from there.
Household-size adjustments
HUD uses a fixed multiplier table to scale income limits up or down for households of different sizes. The 4-person figure is the "base," and the table looks roughly like this:
| Household size | Multiplier of 4-person base |
|---|---|
| 1 person | 70% |
| 2 persons | 80% |
| 3 persons | 90% |
| 4 persons | 100% (base) |
| 5 persons | 108% |
| 6 persons | 116% |
| 7 persons | 124% |
| 8 persons | 132% |
Why your county's number can look different
HUD applies several special rules to keep income limits stable across years and reasonable in low-cost areas: a "national non-metro median" floor for rural counties, year-over-year capping, and "high-housing-cost" adjustments in expensive metros. The result is that the published limit for your county may not be exactly 50% of the raw median family income — but the figure on each city page reflects the published HUD value for the relevant FY.
What counts as income?
HUD uses "annual income," which includes wages, self-employment income, Social Security, pensions, certain assistance payments, and the imputed income from significant assets. Some income sources are excluded — for example, food-stamp benefits and most temporary disaster assistance. PHAs verify income against pay stubs, tax returns, and benefit award letters during the application process.
Where to find your number
Use the state directory to find your city. Each city page lists the 30%, 50%, and 80% income limits for households of 1–8 people in the surrounding county or metro area, drawn from HUD's FY2024 income-limit tables.