Permits through August 2026Yearly permits since 1995St. Charles County index 1975–2025
St. Charles County (100 = first year)United States, rebased to the same startNBER recession
House prices are indexed by county, not by city: this is St. Charles County's FHFA index, with the national index rebased to the same start.
Census Bureau notes: building permit figures cover new privately owned housing units authorised by permit-issuing places; permits do not mean the units were started or completed, and places that report less often than monthly are imputed in monthly totals. FHFA notes: The FHFA HPI is a broad measure of the movement of single-family house prices. The FHFA HPI is a weighted, repeat-sales index, meaning that it measures average price changes in repeat sales or refinancings on the same properties.
OFallon, Missouri (St. Charles County), authorised 515 housing units through building permits in the 12 months to August 2026, −3.0% on the previous 12 months.
279 of those units were single-family houses (54%), 42 were in two- to four-unit buildings and 194 in buildings of five or more units. That is 5.4 units per 1,000 residents, close to the county's 5.0 and well above the state's 2.9.
Since 1995 the place has authorised 26,301 units, with the busiest year 2000 (2,238 units). St. Charles County's FHFA house price index rose +95.1% over the ten years to 2025.
515units permitted, 12 months to August 2026−3.0% on the previous 12 months
279single-family units54% of the total
194units in 5+ unit buildings38% of the total
5.4units per 1,000 residentsSt. Charles County 5.0 · Missouri 2.9
Permits by month and structure type
Housing units authorised in OFallon by month, latest 24 monthssingle-family2+ unit buildings
Units, 12 months to August 2026
OFallon
St. Charles County
Missouri
United States
All housing units
515
2,140
18,495
1,418,086
Single-family (1 unit)
279 (54%)
1,387 (65%)
12,065 (65%)
888,241 (63%)
2 units
6
6
722
34,814
3–4 units
36
61
514
17,298
5 or more units
194 (38%)
686 (32%)
5,194 (28%)
477,733 (34%)
Units per 1,000 residents
5.4
5.0
2.9
4.1
Change on previous 12 months
−3.0%
+22.2%
+4.4%
−0.1%
Permits by year since 1995
Housing units authorised in OFallon by year, 1995–2025single-family2+ unit buildings
26,301 units since 1995; the busiest year was 2000. Annual figures include units imputed for months a place did not report.
Home prices in St. Charles County
FHFA's index for St. Charles County rose +95.1% over the ten years to 2025 (+6.9% a year) and +4.8% in the latest year, against +88.2% and +3.7% for Missouri. Full county page: decade table, peak-to-low declines, every ZIP code and every permit-issuing place in the county.
Questions and answers
How many homes are being built in OFallon, MO?
515 housing units were authorised by building permits in the 12 months to August 2026, against 531 in the previous 12 months.
What kind of housing is being permitted in OFallon?
279 single-family units, 6 in two-unit buildings, 36 in three- and four-unit buildings and 194 in buildings of five or more units.
How does OFallon compare with its county and state?
5.4 units per 1,000 residents in OFallon, 5.0 in St. Charles County and 2.9 in Missouri.
How have home prices moved in St. Charles County?
FHFA's index for St. Charles County rose +95.1% over the ten years to 2025 and +4.8% in the latest year; the county page has the full series.
What does a permit count?
A housing unit authorised by a building permit for new privately owned residential construction, as reported to the Census Bureau Building Permits Survey by the permit-issuing office. Permits are not completions; some permitted units are never built, and places that report only annually are imputed in monthly figures.
Provenance
Permits: US Census Bureau, Building Permits Survey, place-level monthly and annual files through August 2026 (permit office 476500); county and state comparisons from the county and state files. Population: Census Bureau vintage 2025 estimates for incorporated places, matched on FIPS place code where the permit office is one. House price index: Federal Housing Finance Agency. Public domain. Corrections · Building Permits Survey.