Guide
How to find your census tract
The quickest way is to enter your address in the tract lookup, which asks the Census Bureau's geocoder. Every one of the 85,382 tracts also has an 11-digit GEOID and a number that is unique within its county.
How do I read a tract's GEOID?
Take 42091205810: the first two digits (42) are the state, Pennsylvania; the next three (091) the county, Montgomery County; the last six (205810) the tract, which the Census Bureau writes as Census Tract 2058.10: the last two digits are the part after the decimal point. Typing the 11 digits into PlainCities' search opens the tract.
I know the tract number. Why do I get several tracts?
Tract numbers repeat across counties: 279 counties have a "Census Tract 1". Add the county, or use the GEOID. Every county page lists its tracts by number with their figures.
Did my tract change in 2020?
Tracts are redrawn for each census to keep about 4,000 people in each: a growing tract is split and its parts get a suffix after the decimal point (a tract 2058 becomes 2058.01 and 2058.02); shrinking tracts are merged. PlainCities uses the 2020 tracts, which the ACS 2020-2024 figures describe; a tract number from before 2020 may no longer exist.
What figures are published for a tract?
The American Community Survey publishes tracts only as five-year estimates, here 2020 to 2024, because a single year's sample in a tract of about 3,960 residents would be too small. The same measures as for a city are there: population by age, household income, home values and rents, poverty, education, commuting and more, each with its 90% margin of error. The margins are wider than a city's, so PlainCities marks with a ring any figure whose margin is too wide to rely on and never ranks it. 80,478 of the 85,382 tracts have enough reliable figures for a page of their own; the rest are rows of their county's tract table, with their 2020 count and headline figures.
Is a census tract the same as a neighborhood or a ZIP code?
Not quite. A tract is drawn by the Census Bureau with local committees to follow visible features such as roads and rivers and to hold a similar number of people, so it often matches what residents call a neighborhood, but a named neighborhood can span several tracts or share one. A ZIP code is a set of postal delivery routes, drawn by the Postal Service, and its edges do not follow tracts. Tracts never cross a county line, and they cover the whole country, including land outside any city.
What are block groups and blocks?
Each tract is divided into block groups, usually of 600 to 3,000 people, and those into census blocks, the smallest areas the census counts, often a city block. Blocks have 2020 Census counts but no survey estimates; block groups have five-year survey estimates with margins wider still. PlainCities publishes down to the tract, the smallest area whose estimates are reliable often enough to compare.
Source: Census Bureau geographic reference: census tracts and GEOIDs · Census Bureau: understanding GEOIDs