Census Data for Chicago
Population ...
The most recent Census Estimate<1> was for 2019 and it gave Chicago a population of 2,691,497 people.
The last Decennial Census<2> was in 2010, which gave Chicago a population of 2,695,598 people.
The city of Chicago is located in Cook County. The 2010 Census gave Cook County; a population of 5,194,675 people. This means that Chicago had 51.9% of the county's total population, making it Cook's most populous community.
At the same time, Illinois had a population of 12,830,632 people, meaning that Chicago had 21.01% of the total population of Illinois - making it the state's most populous community.
Cook County ...
The community of Chicago is primarily located in Cook County<3> and is the County Seat for Cook County. A portion of Chicago extends into DuPage County.
The county had a population of 5,194,675 people at the 2010 Census. With it's population of 2,695,598 people, Chicago represented 51.9% of the county's total.
For more information, please visit our Census Page for Cook County.
Census-to-Census Observations ...
Introduction ...
When the Census Bureau takes a census count (or enumeration) for Chicago, they start by specifying the boundaries of the area to be counted. This area (or sampling area) is a polygon and its shape can be quite complex - it may or may not match the geographical boundaries of Chicago. It's important to note that from one Census to the next, the shape and location of the polygon can change.
- Continue Reading ...
- Although we don't have specific information about the shape of the polygon for Chicago or how it changed has over time, there is some information that can give us some hints.
- If you need precision or details about the methodology of the Census, you should visit the U.S. Census Bureau for a definitive answer.
Area ...
The area (or polygon) given for the 2010 Census matches that given for the 2000 Census. It's likely that the same polygon was used for the two censuses.
Location ...
While generally coinciding with the GPS location (latitude/longitude) of Chicago, the latitude and longitude given by the Census Bureau actually indicates the GPS location of the polygon for Chicago.
- Continue Reading ...
- For the 2010 Census, the location was given as:
- Lat: 41.837551° (or 41°50'15" N)
- Lon: -87.681844° (or -87°40'54" W)
- For the 2000 Census, the location given was:
- Lat: 41.840675° (or 41°50'26" N)
- Lon: -87.679365° (or -87°40'45" W)
- The difference indicates that the U.S. Census Bureau moved the location of the polygon for the 2010 Census 1,323 feet to the southwest<4> of the location that was used in the 2000 Census.
- The U.S. Geological Survey (USGS) and the U.S. Board on Geographic Names (BGN) have assigned a unique GNIS identifier (#428803) to Chicago. This identifier also marks a GPS point on the map, and that point lies within the boundaries of Chicago. The GNIS point has been mapped to the latitude/longitude:
- Lat: 41.836808° (or 41°50'12" N)
- Lon: -87.684548° (or -87°41'4" W)
- The GPS location given for the 2010 Census lies 782 feet to the east<5> of the point given by the GNIS for Chicago. For more information about this and the relationship of the various Federal Codes, please visit our Misc Page for Chicago.
Miscellaneous Information for Chicago ...
The Federal government has assigned various identifying codes to each community, county and state. At one time or another, the US Census Bureau has used one (or more) of the following identifiers when referring to either Cook County or the city of Chicago:
- The GNIS Codes ...
- The FIPS Codes ...
- An earlier (and largely obsolete) identification method was called the Federal Information Processing Standard (FIPS):
- State Code: 17 (Illinois)
- County Code: 031 (Cook County)
- Place Code: 14000 (Chicago)
- State & County Code: 17/031 (Illinois / Cook County)
- State & Place Code: 17/14000 (Illinois / Chicago)
- Misc. Census Codes ...
- Chicago is located in Census Region #2 (the Midwest Region) and Division #3 (the East North-Central Division).
- The US Postal Service ZIP Code ...
- While some people have used ZIP codes to identify a community, the ZIP codes were actually created to make mail delivery more efficient by grouping addresses together. Although a ZIP Code doesn't specifically identify a city like Chicago, they do identify addresses that are in (or near) the city. It's important to remember that the boundaries of the ZIP Code can be changed, re-assigned, eliminated or overlapped with other ZIP Codes.
- Our list of ZIP codes for Chicago:<6>
- 60601, 60602, 60603, 60604, 60605, 60606, 60607, 60608, 60609, 60610, 60611, 60612, 60613, 60614, 60615, 60616, 60617, 60618, 60619, 60620, 60621, 60622, 60623, 60624, 60625, 60628, 60629, 60630, 60631, 60632, 60633, 60636, 60637, 60638, 60639, 60640, 60643, 60644, 60645, 60646, 60649, 60651, 60652, 60653, 60654, 60655, 60656, 60659, 60660, 60663, 60664, 60667, 60668, 60669, 60670, 60671, 60672, 60673, 60674, 60677, 60678, 60679, 60680, 60683, 60684, 60687, 60690, 60693, 60697, 60699 & 60701.
- Census ZCTA Codes ...
- The US Census Bureau created statistical entities that they call ZIP Code Tabulation Areas (ZCTAs) and these ZCTAs are frequently confused with the ZIP codes that come from the US Postal Service (USPS).
- ZCTAs were first created for the 2000 Census and at that time, they were based upon the USPS ZIP codes. While largely covering the same areas, the boundaries of a ZCTA do not necessarily match the boundaries of a postal ZIP code with the same number. For example, while a postal ZIP code can cross a county or state line, a Census ZCTA can not. They should be treated as separate entities with no correlation between them.
For more information about the various Federal identification codes, please visit our Misc Page for Chicago.
Off-the-Road Links ...
The official website for Chicago: www.cityofchicago.org/
The official website for Cook County: www.co.cook.il.us/
The official website for State of Illinois: https://illinois.gov
The official website of the U.S. Census Bureau
The official website of the U.S. Board on Geographic Names (BGN)
The official website of the U.S. Geological Survey (USGS)
Footnotes ...
| <1> | Every year, the US Census Bureau creates a population estimate for the preceeding year. Keep in mind that this value is an estimate and not an actual count. The most recent Census estimate is for the year 2019. |
| <2> | Every 10 years (eg- 1990, 2000, 2010), the US Census Bureau conducts a Constitutionally-mandated count (or enumeration) of people living within the United States. This count is called a Decennial Census. The last Decennial Census was the 2010 Census, with the next one planned for 2020. |
| <3> | If you're interested in how the shape of Illinois' counties, including Cook, have changed over time, we recommend the Atlas of Historical County Boundaries. |
| <4> | The calculated bearing (or angle) to the 2010 Census location is 149 degrees and a distance of 1,323 feet. |
| <5> | The calculated bearing (or angle) to the GNIS point is 290 degrees and a distance of 782 feet. |
| <6> | When looking for a ZIP Code, whether Chicago or elsewhere, it's always best to check the website of the United States Postal Service (USPS). |