37421 ZIP Code, Chattanooga, TN

37421 is a ZIP code in Chattanooga, Tennessee in Hamilton County. It covers 32 square miles of land. The closest ZIP codes are 30726, 37411 and 37412. 52,985 people live here in 22,278 households, more than in 9 of every 10 Tennessee ZIP codes. At about 1,671 people per square mile it has suburban density, and owners and renters are mixed (60% own). Median household income is $82,517, above the Tennessee median of $69,595.

Quick facts

Key figures

MeasureValue
Residents52,985
Households22,278
Median household income$82,517
Income per person$47,620
Median age40.8
Homeowners60.2%
Median home value$333,700
Median rent$1,405
Bachelor's degree or higher38.8%
Average commute (minutes)19.8
Households with kids under 1825.7%
Moved in the past year17.8%
Below the poverty line10.9%
Broadband internet94.0%
Speak a non-English language at home14.3%

Household income

% of householdsValue
<$10K3.7%
$10–15K3.3%
$15–25K4.8%
$25–35K5.5%
$35–50K10.5%
$50–75K17.4%
$75–100K14.8%
$100–150K19.3%
$150–200K8.3%
$200K+12.4%

Age

% of all residentsValue
<109.4%
10–1911.9%
20–245.9%
25–3415.1%
35–4413.4%
45–5412.8%
55–6412.1%
65–7411.3%
75+8.1%

Tenure

% of housing unitsValue
Owned, with mortgage36.4%
Owned outright20.0%
Rented36.3%
Vacant7.3%

Type of building

% of housing unitsValue
Detached house60.3%
Townhome7.3%
2–4 units5.4%
5–19 units11.7%
20+ units13.7%
Mobile / other1.6%

Businesses in 37421

2,083 business establishments with 42,723 employees (ZIP Codes Business Patterns 2023).

EDDM carrier routes

37421 has 39 USPS carrier routes with 24,780 residential and 2,616 business mailboxes. Open the EDDM route map.

Carrier routes in 37421

37421 has 39 USPS carrier routes (39 city (C)) with 24,780 residential and 2,616 business mailboxes. Routes range from 239 homes (C035) to 1,127 homes (C039); the median route has 604 homes. The Census counted 22,278 households in 37421 (2020–2024 average); USPS counts current mailboxes, including new and vacant homes.

Homes per routeRoutes
1–2491
250–49910
500–74917
750–9999
1,000–1,4992
1,500+0

Best routes in 37421 for…

Most businesses

For B2B offers: office supplies, cleaning, IT, catering and commercial services.

  1. Route C019 — USPS business mailboxes 349, 257 homes
  2. Route C020 — USPS business mailboxes 337, 340 homes
  3. Route C035 — USPS business mailboxes 309, 239 homes
  4. Route C050 — USPS business mailboxes 254, 504 homes
  5. Route C003 — USPS business mailboxes 230, 522 homes

Select these 5 routes on the route map

Every carrier route in 37421

RouteTypeHomesBusinessesEst. median incomeEst. ownersEst. families with kidsEst. moved in past year
C002City5721$149,360———
C003City522230$45,328———
C005City8678$98,505———
C007City8328$111,892———
C008City91582$59,010———
C009City74231$70,498———
C010City418158$49,578———
C011City68715$84,396———
C012City3690$168,053———
C013City5570$185,024———
C014City751102$45,328———
C015City4998$168,053———
C016City7398$67,181———
C017City4680$117,111———
C019City257349$34,598———
C020City340337————
C021City5790$100,996———
C023City62013$115,229———
C024City3821$114,596———
C025City71112$45,328———
C026City74711$69,912———
C027City5271$142,653———
C029City96034$63,245———
C030City284156$77,469———
C031City4350$102,617———
C034City60418$62,916———
C035City239309$111,892———
C037City85053$44,875———
C039City1,12746$111,892———
C041City70623$98,505———
C042City47314$114,596———
C043City885121$63,245———
C044City52716$165,241———
C045City5451$165,241———
C046City92311$111,892———
C047City605129$165,241———
C048City1,01537$44,875———
C049City99719$71,848———
C050City504254$22,820———

Income, owners, families and movers are estimates for each route (how we estimate them); mailbox counts are current USPS figures. Open 37421 on the EDDM route map.

How route demographics are estimated

Mailbox counts come from USPS; demographics are estimates

The number of homes and businesses on each carrier route is the current USPS EDDM count. The Census Bureau does not publish figures for carrier routes, so income, homeownership, ages, families, movers and housing age on a route are EDDM2GO estimates built from Census block groups (neighborhood areas of roughly 600 to 3,000 people).

How a route gets its figures: the block-group length-share method

We trace each route's streets every 25 meters and record which block group each stretch falls in. The route's homes are spread along its streets in proportion to length, so a route with 60% of its street length in one block group is assumed to have 60% of its homes there. Each block group then contributes its Census counts in proportion to the share of its housing units that sit on the route (capped at the whole block group). Medians are recalculated from the combined income, home-value and age brackets, the way the Census Bureau computes them, not averaged.

Margins of error

Census survey figures carry a margin of error at 90% confidence; we carry it through the calculation and show it as ±. Our margins treat the route-to-block-group split as exact, so the real uncertainty is larger. Routes with fewer than 100 estimated households, large margins, or streets we could not place are flagged.

Different years

USPS mailbox counts are current. Census figures are 5-year averages for 2020–2024, so a new subdivision may have more homes on the route today than the Census counted. Use the route figures to compare routes with each other, not as an exact head count.

Why some routes show identical figures

Two routes that run through the same block group get the same percentages and medians, because the Census publishes one set of figures for the whole block group. Their mailbox counts still differ, and those are exact.

Route and mailbox counts: USPS EDDM route data. Route demographics: EDDM2GO estimates from U.S. Census Bureau American Community Survey 5-year block-group data (2020–2024) and 2024 cartographic block-group boundaries. This product uses the Census Bureau Data API but is not endorsed or certified by the Census Bureau.

Nearby ZIP codes

Areas that include 37421

Where it ranks

Mail every home in 37421

Route counts on this page price as Full Service 6.5 × 9 postcards: we print, bundle by carrier route and hand the mailing to USPS. Prefer to take it to the Post Office yourself? Print only costs less and you pay postage at drop-off.

EDDM guides

ZIP code statistics describe the Census ZIP Code Tabulation Area (ZCTA) 37421, which approximates the USPS ZIP code area. Census figures: American Community Survey 5-year estimates, 2020–2024.

Frequently asked questions

What city is 37421 in?
37421 is a Chattanooga, TN mailing address. By land area, 77% lies inside Chattanooga; the rest is outside any Census-defined city or community.
What county is 37421 in?
37421 is in Hamilton County.
What is the population of 37421?
About 52,985 people (±2,162), according to the Census Bureau's American Community Survey 5-year estimates for 2020–2024. The 2020 Census counted 51,686.
What is the median household income in 37421?
$82,517 (±$3,937), compared with $69,595 for Tennessee as a whole. Half the households in the ZIP code earn more and half earn less.
How many carrier routes and mailboxes are in 37421?
39 USPS carrier routes with 24,780 residential and 2,616 business mailboxes (27,401 in all), from the route data stored by EDDM2GO. An EDDM mailing can target any combination of these routes.
What ZIP codes are near 37421?
The closest, measured center to center: 30726 (3.7 mi), 37411 (4.3 mi, Chattanooga), 37412 (4.7 mi, East Ridge), 37416 (4.9 mi, Chattanooga), 37315 (5.9 mi, Collegedale) and 37406 (6.1 mi, Chattanooga).

This product uses the Census Bureau Data API but is not endorsed or certified by the Census Bureau.