Saint Louis, MO · standard
ZIP Code 63121
St. Louis County, Missouri - Census ACS demographics, housing tenure, and business patterns, benchmarked against every US ZIP.
- 26,602
- 1,431/sq mi High-density area
- $42,701
- Median income Below-median income area
- $95,600
- Median home value Below-median home value
- 24.2%
- Bachelor's or higher Near-average bachelor's attainment
National ZIP placement
Saint Louis pairs one of the lowest household incomes in the country with among the most affordable home values nationally, in a low-density, mixed-tenure area.
- 7th pct
- household income, US ZIPs
- 8th pct
- home value, US ZIPs
- 1,431
- people per sq mi
- 52%
- owner-occupied homes
Source: U.S. Census Bureau ACS 5-Year Estimates (2019–2023). Percentiles rank ZIP 63121 against every reporting US ZIP.
FHFA HPI release change
What changed in the latest House Price Index year
- FHFA House Price Index values in ZIP 63121 (Saint Louis, MO) rose +7.7% from 2023 to 2024. The all-transactions index moved from 167.6 in 2023 to 180.5 in 2024 (2000 = 100).
ZIP code 63121 is a densely settled ZIP (a standard USPS delivery area) in Saint Louis, St. Louis County, Missouri, with 26,602 residents across 18.6 square miles, a density of 1,431 people per square mile, in the Chicago time zone.
ZIP 63121 reports a modest median household income of $42,701 (36% below the average Missouri ZIP), while per-capita income is $27,628. Economic pressure is pronounced: 25.6% of residents are below the poverty line and unemployment is 12.3%. Home values sit below the statewide ZIP benchmark: the median is $95,600 (50% below the average Missouri ZIP), and median rent is $985; owner occupancy is 51.6%.
Educational attainment sits below the national norm: 24.2% of adults hold a bachelor's degree or higher, the median age is 33.2, and the average commute is 24 minutes. The page also surfaces 10 ZIP codes within roughly 10 miles and 6 more in St. Louis County, so 63121 can be compared with both its immediate and county-level context.
Every figure on this page is sourced from the U.S. Census Bureau American Community Survey 5-Year Estimates (including median rent) and the FHFA House Price Index, no estimates, no proprietary scoring. Verify with Census →
Top industries in ZIP 63121
Top 5 sectors by establishment count in Saint Louis, MO
Which industries have the most business establishments in ZIP 63121.
- Health care and social assistance
Health care and social assistance
112 establishments
- Retail trade 43
Retail trade
43 establishments
- Other services (except public administration) 29
Other services (except public administration)
29 establishments
- Accommodation and food services 26
Accommodation and food services
26 establishments
- Finance and insurance 24
Finance and insurance
24 establishments
What this shows Establishment counts come from the Census ZIP Code Business Patterns program, which counts physical business locations rather than employees or revenue.
Source: U.S. Census Bureau, American Community Survey 5-Year Estimates + ZIP Code Business Patterns + FHFA HPI ACS demographics and median rent, ZBP business establishments, FHFA HPI for ZIP 63121, Saint Louis, MO · 2023 Census ACS 5-Year Estimates use a rolling 60-month sample for stable small-geography estimates; ZBP updated annually; FHFA HPI updated quarterly/annually.
Quick Facts
26,602
Population
18.6
Area (sq mi)
1,431
People / sq mi
Chicago
Time Zone
standard
ZIP Type
Who lives in ZIP 63121?
33.2
Median Age
44.0%
Male
56.0%
Female
3.2%
Foreign-Born
Hispanic or Latino is an ethnicity category from the Census Bureau and may overlap with other categories above.
Source: U.S. Census Bureau, ACS 5-Year Estimates (2023)
How much do residents earn?
$42,701
Median Household Income
-36% vs state ZIP avg
$27,628
Per Capita Income
25.6%
Poverty Rate
12.3%
Unemployment Rate
23.8 min
Mean Commute Time
How ZIP 63121 ranks among Missouri ZIPs
Saint Louis, MO household income vs. every Missouri ZIP code
Median household income among 948 reporting Missouri ZIPs (this ZIP's population is too small for a reliable national-corpus placement)
$42,701 10th percentile higher than 10% of 948 Missouri ZIPs
Each bar is a $20K-wide band; taller bars hold more Missouri ZIPs. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count, share, and where it sits relative to this entry.
Source U.S. Census Bureau, ACS 5-Year Estimates · 2019–2023
Source: U.S. Census Bureau, ACS 5-Year Estimates (2023)
What is the education profile here?
Source: U.S. Census Bureau, ACS 5-Year Estimates (2023)
What does housing look like?
Housing stock: occupied vs vacant
13,008housing units
13,008
Total Housing Units
11,142
Occupied Units
1,866
Vacant Units
2.15
Avg Household Size
Occupancy Type
$95,600
Median Home Value
-50% vs state ZIP avg
$985
Median Rent
1953
Median Year Built
Source: U.S. Census Bureau, ACS 5-Year Estimates (2023)
How have home values changed over time?
FHFA House Price Index, annual appreciation data based on repeat sales and appraisals
+7.7%
YoY Change (2024)
180
HPI Index (2000 = 100)
+80%
Total Change Since 2000
Home values in ZIP 63121 have increased 7.7% over the past year (2024). Since 2000, this ZIP has seen +80% cumulative appreciation.
| Year | Annual Change | HPI Index |
|---|---|---|
| 2020 | +9.0% | 123 |
| 2021 | +10.4% | 135 |
| 2022 | +18.4% | 160 |
| 2023 | +4.6% | 168 |
| 2024 | +7.7% | 180 |
Source: Federal Housing Finance Agency (FHFA) House Price Index, All-Transactions, Five-Digit ZIP Codes (Developmental Index). Index base = 100 in year 2000. Data through 2024. ZIP codes with few transactions may show missing values.
What businesses operate in this ZIP?
Census Bureau data shows 315 business establishments in ZIP 63121, employing approximately 4,540 people with a combined annual payroll of $364,428,000.
315
Businesses
4,540
Employees
$364.4M
Annual Payroll
15
Industry Sectors
| Industry | Establishments | % of Total |
|---|---|---|
| Health care and social assistance | 112 | 35.6% |
| Retail trade | 43 | 13.7% |
| Other services (except public administration) | 29 | 9.2% |
| Accommodation and food services | 26 | 8.3% |
| Finance and insurance | 24 | 7.6% |
| Construction | 14 | 4.4% |
| Administrative and support and waste management and remediation services | 14 | 4.4% |
| Professional, scientific, and technical services | 13 | 4.1% |
| Transportation and warehousing | 7 | 2.2% |
| Real estate and rental and leasing | 7 | 2.2% |
| Wholesale trade | 6 | 1.9% |
| Management of companies and enterprises | 6 | 1.9% |
| Educational services | 5 | 1.6% |
| Arts, entertainment, and recreation | 5 | 1.6% |
| Manufacturing | 4 | 1.3% |
Source: U.S. Census Bureau, ZIP Code Business Patterns (ZBP), 2023. Employment figures may include noise for disclosure avoidance.
Nearby ZIP Codes
Want a side-by-side? Compare 63121 vs 63133 →
ZIP 63121 vs its nearest neighbors, by population
Resident population of this ZIP and the closest reporting ZIP codes within ~10 miles.
- 63136
Saint Louis (63136)
48,560 residents
- 63114
Saint Louis (63114)
36,201 residents
- 63130
Saint Louis (63130)
30,084 residents
- 63121
Saint Louis (63121)
26,602 residents
- 63135
Saint Louis (63135)
21,334 residents
- 63115
Saint Louis (63115)
20,775 residents
- 63112
Saint Louis (63112)
20,368 residents
- 63134 13,638
Saint Louis (63134)
13,638 residents
- 63120 10,296
Saint Louis (63120)
10,296 residents
What this shows Among its immediate neighbors, ZIP 63121 ranks #4 by population - useful context the national average alone can't give.
ZIP 63121 vs its nearest neighbors, by median income
Median household income of this ZIP and the closest reporting ZIP codes within ~10 miles.
- 63130
Saint Louis (63130)
$85,823 median income
- 63114
Saint Louis (63114)
$55,870 median income
- 63135
Saint Louis (63135)
$52,328 median income
- 63140
Saint Louis (63140)
$45,568 median income
- 63112
Saint Louis (63112)
$45,542 median income
- 63134
Saint Louis (63134)
$44,680 median income
- 63121
Saint Louis (63121)
$42,701 median income
- 63136
Saint Louis (63136)
$41,154 median income
- 63133
Saint Louis (63133)
$39,293 median income
What this shows By household income, ZIP 63121 ranks #7 of 9 neighboring ZIPs, local affluence varies block to block, not just metro to metro.
| ZIP Code | City | Population | Distance |
|---|---|---|---|
| 63133 | Saint Louis, MO | 8,161 | 1.8 mi |
| 63135 | Saint Louis, MO | 21,334 | 3.0 mi |
| 63140 | Saint Louis, MO | 294 | 2.5 mi |
| 63120 | Saint Louis, MO | 10,296 | 2.4 mi |
| 63130 | Saint Louis, MO | 30,084 | 3.2 mi |
| 63114 | Saint Louis, MO | 36,201 | 3.3 mi |
| 63112 | Saint Louis, MO | 20,368 | 3.5 mi |
| 63136 | Saint Louis, MO | 48,560 | 3.4 mi |
| 63134 | Saint Louis, MO | 13,638 | 3.5 mi |
| 63115 | Saint Louis, MO | 20,775 | 3.7 mi |
Nationwide ZIPs with similar ACS profiles
Two Census-derived peer sets for ZIP 63121, both outside MO so the neighborhoods are not geographic containment (Nearby and same-county blocks stay local).
Similar population
Nearest cross-state ZIPs by resident population (26,602 here; floor ≥1,000).
Similar median household income
Nearest cross-state ZIPs by ACS median household income.
More ZIP Codes in St. Louis County
Related Areas
Frequently Asked Questions
What county is ZIP code 63121 in?
ZIP code 63121 (Saint Louis) is located in St. Louis County, Missouri. St. Louis County contains multiple ZIP codes, see the full list at /counties/st-louis-mo-29189.
What is the population of ZIP code 63121?
ZIP code 63121 in Saint Louis, MO has a population of 26,602 according to the Census Bureau ACS 2023 estimates.
What is the median household income in ZIP 63121?
The median household income in ZIP 63121 is $42,701, which is 44% below the national average of $76,288.
What is the average home value in ZIP 63121?
The median home value in ZIP 63121 is $95,600, which is 66% below the national average of $278,155.
What is the demographic makeup of ZIP 63121?
The largest racial group in ZIP 63121 is African American at 78.8%. Hispanic or Latino residents make up 2.5% of the population.
How many businesses are in ZIP code 63121?
ZIP code 63121 has 315 business establishments employing approximately 4,540 people, according to Census Bureau ZIP Code Business Patterns (ZBP) 2023 data.
What are the main industries in ZIP code 63121?
The top industries by establishment count in ZIP 63121 are: Health care and social assistance (112), Retail trade (43), Other services (except public administration) (29). There are 15 industry sectors represented in total.
How have home values changed in ZIP code 63121?
According to the FHFA House Price Index, home values in ZIP 63121 increased by 7.7% in 2024. Since 2000, home values in this ZIP have appreciated by approximately 80%. This is a developmental index based on repeat sales and appraisal data from Fannie Mae and Freddie Mac.
What is the education level in ZIP code 63121?
In ZIP code 63121, 60.1% of residents aged 25+ have a high school diploma or higher, and 24.2% hold a bachelor's degree or higher. These figures come from the Census Bureau ACS 5-Year Estimates (2023).
What is the average commute time in ZIP 63121?
The mean commute time for workers in ZIP code 63121 is 23.8 minutes according to Census ACS data. The national average is roughly 26 minutes, so commuters here spend less time traveling to work than typical.
What percentage of residents own vs. rent in ZIP 63121?
In ZIP code 63121, approximately 51.6% of occupied housing units are owner-occupied and 48.4% are renter-occupied, based on Census ACS 2023 data.
What is the poverty rate in ZIP code 63121?
The poverty rate in ZIP code 63121 is 25.6% according to Census Bureau ACS 2023 estimates. This measures the percentage of the population living below the federal poverty threshold.
Related
Take this with you
What to do with ZIP 63121's numbers, next.
- See how ZIP 63121 compares to a neighboring ZIP code on the same Census fields Compare this ZIP
- Check where Saint Louis, MO ranks among every U.S. ZIP code on income, education, or homeownership View national rankings
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ZIP Code Tabulation Areas (ZCTAs) are Census Bureau approximations of USPS ZIP codes; figures describe the ZCTA area, not any single address within it.