78621 ZIP Code, Elgin, TX

78621 is a ZIP code in Elgin, Texas — mostly in Bastrop County (63% of its land), with smaller parts in Travis, Williamson and Lee counties. It covers 178 square miles of land, centered about 23 miles east of downtown Austin. The closest ZIP codes are 78650, 78615 and 78653. 30,411 people live here in 10,175 households. With about 171 people per square mile it is lightly settled, and most homes are owner-occupied (81%). Median household income is $98,534, above the Texas median of $78,476.

Quick facts

Key figures

MeasureValue
Residents30,411
Households10,175
Median household income$98,534
Income per person$38,211
Median age36.2
Homeowners81.1%
Median home value$320,800
Median rent$1,387
Bachelor's degree or higher24.3%
Average commute (minutes)37.5
Households with kids under 1835.7%
Moved in the past year9.4%
Below the poverty line6.4%
Broadband internet89.1%
Speak a non-English language at home44.8%

Household income

% of householdsValue
<$10K3.4%
$10–15K0.9%
$15–25K4.5%
$25–35K6.0%
$35–50K5.8%
$50–75K16.0%
$75–100K14.7%
$100–150K24.7%
$150–200K11.7%
$200K+12.3%

Age

% of all residentsValue
<1017.0%
10–1913.0%
20–245.1%
25–3412.8%
35–4414.1%
45–5411.5%
55–6414.1%
65–748.3%
75+4.2%

Tenure

% of housing unitsValue
Owned, with mortgage44.9%
Owned outright30.5%
Rented17.0%
Vacant7.6%

Type of building

% of housing unitsValue
Detached house69.6%
Townhome1.9%
2–4 units3.8%
5–19 units0.5%
20+ units1.1%
Mobile / other23.1%

Businesses in 78621

401 business establishments with 4,513 employees (ZIP Codes Business Patterns 2023).

EDDM carrier routes

78621 has 15 USPS carrier routes with 12,832 residential and 423 business mailboxes. Open the EDDM route map.

Carrier routes in 78621

78621 has 15 USPS carrier routes (2 city (C), 13 rural (R)) with 12,832 residential and 423 business mailboxes. Routes range from 592 homes (C001) to 1,255 homes (R013); the median route has 786 homes. The Census counted 10,175 households in 78621 (2020–2024 average); USPS counts current mailboxes, including new and vacant homes.

Homes per routeRoutes
1–2490
250–4990
500–7495
750–9996
1,000–1,4994
1,500+0

Best routes in 78621 for…

Highest income

For bigger-ticket offers: remodeling, pools, financial planning, private schools.

  1. Route R005 — Est. median household income $116,766, 758 homes
  2. Route R007 — Est. median household income $111,480, 800 homes
  3. Route R004 — Est. median household income $109,265, 642 homes
  4. Route R009 — Est. median household income $106,449, 956 homes
  5. Route R013 — Est. median household income $105,836, 1,255 homes

Select these 5 routes on the route map

Often mailed by: Home services EDDM, Real estate EDDM postcards, Landscaping and lawn care mailers

Most families with kids

For tutoring, youth sports, pediatric dental, child care and family dining.

  1. Route R008 — Est. families with children under 18 56.7%, 1,101 homes
  2. Route R010 — Est. families with children under 18 52.0%, 911 homes
  3. Route R014 — Est. families with children under 18 45.0%, 1,136 homes
  4. Route R006 — Est. families with children under 18 43.2%, 759 homes
  5. Route R009 — Est. families with children under 18 37.7%, 956 homes

Select these 5 routes on the route map

Often mailed by: Dental practice EDDM, Healthcare and clinic mailers

Most homeowners

Owners decide on roofs, HVAC, lawns, solar and insurance; renters usually can't.

  1. Route R003 — Est. owner-occupied homes 94.7%, 703 homes
  2. Route R011 — Est. owner-occupied homes 89.4%, 786 homes
  3. Route R004 — Est. owner-occupied homes 86.6%, 642 homes
  4. Route R009 — Est. owner-occupied homes 85.9%, 956 homes
  5. Route R007 — Est. owner-occupied homes 84.6%, 800 homes

Select these 5 routes on the route map

Often mailed by: Roofing direct mail, HVAC postcards

Most new movers

New residents are still choosing a dentist, a gym and a lawn service.

  1. Route R003 — Est. residents who moved in the past year 15.9%, 703 homes
  2. Route R008 — Est. residents who moved in the past year 15.0%, 1,101 homes
  3. Route R014 — Est. residents who moved in the past year 14.9%, 1,136 homes
  4. Route R011 — Est. residents who moved in the past year 14.3%, 786 homes
  5. Route R006 — Est. residents who moved in the past year 13.3%, 759 homes

Select these 5 routes on the route map

Often mailed by: Restaurant EDDM menus and offers, Gym and fitness mailers

Newest homes

Newer subdivisions: landscaping, window treatments, fencing, security, home warranties.

  1. Route R008 — Est. homes built 2010 or later 49.3%, 1,101 homes
  2. Route R010 — Est. homes built 2010 or later 43.7%, 911 homes
  3. Route R014 — Est. homes built 2010 or later 37.4%, 1,136 homes
  4. Route R001 — Est. homes built 2010 or later 31.3%, 709 homes
  5. Route R009 — Est. homes built 2010 or later 29.9%, 956 homes

Select these 5 routes on the route map

Most businesses

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

  1. Route C002 — USPS business mailboxes 173, 1,011 homes
  2. Route R013 — USPS business mailboxes 83, 1,255 homes
  3. Route R011 — USPS business mailboxes 74, 786 homes
  4. Route C001 — USPS business mailboxes 32, 592 homes
  5. Route R009 — USPS business mailboxes 13, 956 homes

Select these 5 routes on the route map

Every carrier route in 78621

RouteTypeHomesBusinessesEst. median incomeEst. ownersEst. families with kidsEst. moved in past year
C001City59232$85,14970.6%32.1%12.5%
C002City1,011173$84,21773.8%26.6%10.8%
R001Rural7095$103,61783.2%36.3%5.4%
R003Rural7036$72,26294.7%20.9%15.9%
R004Rural6421$109,26586.6%36.9%8.0%
R005Rural7583$116,76684.1%33.2%5.3%
R006Rural7596$91,28373.7%43.2%13.3%
R007Rural8009$111,48084.6%28.5%5.9%
R008Rural1,1013$77,85881.0%56.7%15.0%
R009Rural95613$106,44985.9%37.7%7.3%
R010Rural9114$74,46976.8%52.0%11.8%
R011Rural78674$75,29089.4%29.1%14.3%
R012Rural7133$96,33181.2%36.0%7.8%
R013Rural1,25583$105,83681.8%33.0%7.4%
R014Rural1,1368$76,96373.9%45.0%14.9%

Income, owners, families and movers are estimates for each route (how we estimate them); mailbox counts are current USPS figures. Open 78621 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 78621

Where it ranks

Mail every home in 78621

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) 78621, which approximates the USPS ZIP code area. Census figures: American Community Survey 5-year estimates, 2020–2024.

Frequently asked questions

What city is 78621 in?
78621 is a Elgin, TX mailing address. By land area, 4% lies inside Elgin; the rest is outside any Census-defined city or community.
What county is 78621 in?
78621 is mostly in Bastrop County (63% of its land), with smaller parts in Travis, Williamson and Lee counties.
What is the population of 78621?
About 30,411 people (±2,687), according to the Census Bureau's American Community Survey 5-year estimates for 2020–2024. The 2020 Census counted 27,275.
What is the median household income in 78621?
$98,534 (±$7,172), compared with $78,476 for Texas as a whole. Half the households in the ZIP code earn more and half earn less.
How many carrier routes and mailboxes are in 78621?
15 USPS carrier routes with 12,832 residential and 423 business mailboxes (13,257 in all), from the route data stored by EDDM2GO. An EDDM mailing can target any combination of these routes.
What ZIP codes are near 78621?
The closest, measured center to center: 78650 (8.7 mi, McDade), 78615 (8.9 mi, Coupland), 78653 (9.6 mi, Manor), 78602 (14.3 mi, Camp Swift), 76578 (15.5 mi, Thrall) and 78660 (15.7 mi, Pflugerville).

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