O’FALLON, Mo. – Believe it or not, the St. Louis Metropolitan Area’s most-populated suburb is closing in on a major milestone: 100,000 residents.
According to U.S. Census figures, the city of O’Fallon, Missouri, has an estimated population of 95,355 residents as of July 1, 2024, the latest available such data.
That’s up from 91,375 at the start of the 2020s decade and 79,329 at the start of the 2010s decade, per Census figures.
After a major population boom from 1990 to 2010, when the city grew from around 18,000 residents, O’Fallon has seen steady and consistent population growth in recent years.
Over the last decade and a half, on average, O’Fallon’s population has grown by around 1% annually. The growth trend has mostly held true on a year-to-year basis, according to Census, with several years of population gains between hundreds to a few thousand residents since 2010.
So let’s say 1% is the clip of expected growth in O’Fallon for the foreseeable future… Right now, that’s slightly lower than the average growth rates of the last 5-year, 10-year and 15-year periods.
At that rate, how long might it take O’Fallon to reach 100,000 residents?
If the math holds true, it’s possible this happens by the end of this decade or near the start of the new one.
If the 1% annual pace continues, O’Fallon is on track to surpass 100,000 residents within the next five years. Current projections suggest the population would reach around 100,248 residents by 2029.
Of course, future growth will depend on factors like housing development, job opportunities and whether families continue to settle and grow in O’Fallon. But for now, the trajectory is clear, and O’Fallon appears well on its way to a six-figure population.
And if O’Fallon eventually reaches that mark, it would become just the seventh Missouri city with a population of at least 100,000 and the only one in the Greater St. Louis Area outside of the City of St. Louis to have such a distinction.