Lake County population surpasses 500,000 for the first time in 40+ years

While a symbolic milestone, this represents part of a larger trend of Northwest Indiana attracting and retaining population.

Note: This post is an extension and expansion of an article published in the Northwest Indiana Times by Joseph Pete to provide more background and data than possible in that article.

Last week the U.S. Census Bureau released their county-level population estimates for 2023. In these data, the population of Lake County rose to 500,598. This marks the first time the U.S. Census Bureau has reported a population of over half a million for the Lake County since 1980.

Historically, the population of Lake County peaked in 1970 at 546,253 people. In the decades that followed, the collapse of American manufacturing and steel industries sent the population of Lake County plummeting 13% over 20 years. For contrast, the national population and population of Indiana rose 22.3% and 6.7%, respectively, over the same period.¹ The figure below shows the population of Lake County from 1960 to 2023.

Figure 1: Lake County, Indiana Population (1960-2023)

While Lake County is still below its historical population peak, it’s important to celebrate significant milestones as we narrow this gap. This is especially true when there are indications that this population growth represents part of a larger trend of attracting and retaining population, not just in Lake County but across the entire Northwest Indiana region.

While Lake County is still 8% below its historical peak, the population of the broader Northwest Indiana region continues grow and set new records. In 2023, the population of the 4-county region (Lake, Porter, Newton and Jasper) of Northwest Indiana² was 723,428.

Figure 2: Northwest Indiana Population (1960-2023)

If we expand our definition of Northwest Indiana to include other counties and cover the entire Indiana Economic Growth Region 1 (EGR1), the picture is similar. With a population of 870,725, EGR1 is the second most populous economic growth region in Indiana.

Migration is driving the population growth

All of the overall population growth in Lake County that occurred between 2020 and 2023 can be attributed to migration. During this period, the natural change in population (births minus deaths) was a negative 1,319, while migration brought in a net positive of 2,945 new residents.

A similar story is true for the broader Northwest Indiana region as well. All of the population growth for the 7-county region (EGR1) of Northwest Indiana that occurred between 2020 and 2023 can be attributed to migration. During this period, the natural change in population was a negative 3,667, while migration brought in a net positive of 7,083.

Northwest Indiana has long been a stepping stone out of Chicago and this continues today. However, this recent positive population growth is directly connected with retaining more of the people who move into Northwest Indiana, rather than having them live here for a few years and continue on to other parts of the United States. A few months ago I wrote a post about this trend: More People are Choosing to Live in Northwest Indiana and that's a Very Good Sign. Below you can find an updated figure from that post with the addition of data for 2023.

Additional reading

• “Northwest Indiana reaches record population as Lake County surpasses 500,000 people for first time since 1982,” The Times of Northwest Indiana, 3/26/2025

• Pollak, M. (2016), “Socioeconomic and Demographic Trends of Northwest Indiana since 1970,” Journal of the Indiana Academy of the Social Sciences, Vol. 19, No. 1: p88-109.

• More People are Choosing to Live in Northwest Indiana and that's a Very Good Sign, The Region Economist, 12/5/2023

A note about population estimates

Population estimates are, as their name indicates, estimates. The U.S. Census Bureau does not actually track down and count every single person to determine population, as much as we wish they could. As a result, the 2023 population estimate of 500,598 for Lake County has a margin of error. While the trend is clear and the county has almost certainly surpassed a population of 500,000, it’s not possible to be precise in exactly when this occurred.

1. For more background on this decline in population, you can refer to an article I published several years ago on this topic: Socioeconomic and Demographic Trends of Northwest Indiana since 1970.

2. This 4-county region of Northwest Indiana was formerly called the “Gary, IN Division” but was renamed in 2023 ‘to the more verbose “Lake County-Porter County-Jasper County, IN Division”’.