LIHTC Guide
Sign in Subscribe Help

Tools

DDA & QCT Lookup

Sign in to favorite your most-used tools and reorder them to match your workflow.

Enter a complete address including street, city, state, and ZIP code

Looking up designations…

Qualified Census Tract

Difficult Development Area

What This Tool Checks

  • Qualified Census Tracts (QCTs): census tracts where at least 50% of households have incomes below 60% of the Area Median Gross Income, or where the poverty rate is at least 25%. HUD designates them by 2020 census tract.
  • Difficult Development Areas (DDAs): areas with high construction, land, and utility costs relative to incomes. In metropolitan areas HUD designates Small DDAs by ZIP Code Tabulation Area (ZCTA); in nonmetropolitan areas DDAs are designated by county.
  • Basis boost: buildings in a QCT or DDA may qualify for an increase of up to 30% in eligible basis under IRC §42(d)(5)(B).

How It Works

  • Address or location: the U.S. Census Geocoder finds the 2020 census tract, county, ZCTA, and metro area for the address, then the tool checks each against HUD’s lists for the selected year.
  • Census Tract: enter the 11-digit tract code (state, county, tract) to check QCT status. DDA status is shown when the county is nonmetropolitan.
  • ZIP Code: checks metro Small DDA status for the ZCTA. A ZIP cannot determine QCT status because ZIPs cross tract lines.
  • County FIPS: checks nonmetro DDA status and shows how many QCTs are in the county.
  • ZIPs in more than one metro area: some ZCTAs cross HUD metro area lines and are designated in one area but not another. For an address, the tool uses the area that matches the property’s metro area; otherwise it lists each area.

Which Year Applies

  • HUD publishes designations each year. They generally apply to allocations made, or bonds issued, in that calendar year.
  • HUD’s rules can preserve an earlier designation in some cases, such as when a complete application was submitted while the area was designated. Check the current HUD notice and your allocating agency’s guidance before relying on a prior year.

Limitations

  • State-designated basis boost areas (IRC §42(d)(5)(B)(v)) are set by each allocating agency and are not covered here.
  • Address matching can be imprecise near tract or ZIP boundaries. Confirm results on HUD’s official maps for any property decision.
  • Data comes from HUD USER (huduser.gov/portal/qct). This tool is not affiliated with HUD.