78578 ZIP Code, Port Isabel, TX
78578 is a ZIP code in Port Isabel, Texas in Cameron County. It covers 57 square miles of land. The closest ZIP codes are 78521, 78566 and 78526. 10,016 people live here in 4,379 households. With about 176 people per square mile it is lightly settled, and most homes are owner-occupied (75%). Median household income is $51,880, well below the Texas median of $78,476; the median age is 49.0, older than most ZIP codes.
Quick facts
- Mailing city: Port Isabel, TX
- County: Cameron County
- Land area: 57 sq mi
- Population: 10,016
- Median household income: $51,880
- Carrier routes: 5 (4,061 homes)
Key figures
| Measure | Value |
|---|---|
| Residents | 10,016 |
| Households | 4,379 |
| Median household income | $51,880 |
| Income per person | $37,249 |
| Median age | 49 |
| Homeowners | 74.6% |
| Median home value | $196,200 |
| Median rent | $749 |
| Bachelor's degree or higher | 28.6% |
| Average commute (minutes) | 17.3 |
| Households with kids under 18 | 24.8% |
| Moved in the past year | 11.9% |
| Below the poverty line | 27.0% |
| Broadband internet | 81.0% |
| Speak a non-English language at home | 47.2% |
Household income
| % of households | Value |
|---|---|
| <$10K | 12.1% |
| $10–15K | 2.9% |
| $15–25K | 13.5% |
| $25–35K | 11.3% |
| $35–50K | 7.9% |
| $50–75K | 11.6% |
| $75–100K | 11.4% |
| $100–150K | 12.9% |
| $150–200K | 8.1% |
| $200K+ | 8.2% |
Age
| % of all residents | Value |
|---|---|
| <10 | 9.8% |
| 10–19 | 11.5% |
| 20–24 | 6.4% |
| 25–34 | 10.2% |
| 35–44 | 8.2% |
| 45–54 | 11.9% |
| 55–64 | 14.9% |
| 65–74 | 11.5% |
| 75+ | 15.8% |
Tenure
| % of housing units | Value |
|---|---|
| Owned, with mortgage | 20.6% |
| Owned outright | 30.0% |
| Rented | 17.1% |
| Vacant | 32.3% |
Type of building
| % of housing units | Value |
|---|---|
| Detached house | 47.0% |
| Townhome | 5.7% |
| 2–4 units | 8.3% |
| 5–19 units | 5.4% |
| 20+ units | 6.1% |
| Mobile / other | 27.3% |
Businesses in 78578
211 business establishments with 1,997 employees (ZIP Codes Business Patterns 2023).
- Accommodation and Food Services: 40
- Retail Trade: 32
- Agriculture, Forestry, Fishing and Hunting: 22
- Other Services (except Public Administration): 16
- Health Care and Social Assistance: 15
- Professional, Scientific, and Technical Services: 13
- Real Estate and Rental and Leasing: 12
- Construction: 11
EDDM carrier routes
78578 has 5 USPS carrier routes with 4,061 residential and 247 business mailboxes. Open the EDDM route map.
Carrier routes in 78578
78578 has 5 USPS carrier routes (2 city (C), 3 highway contract (H)) with 4,061 residential and 247 business mailboxes. Routes range from 399 homes (C003) to 1,589 homes (C001); the median route has 690 homes. The Census counted 4,379 households in 78578 (2020–2024 average); USPS counts current mailboxes, including new and vacant homes.
| Homes per route | Routes |
|---|---|
| 1–249 | 0 |
| 250–499 | 1 |
| 500–749 | 2 |
| 750–999 | 1 |
| 1,000–1,499 | 0 |
| 1,500+ | 1 |
Best routes in 78578 for…
Highest income
For bigger-ticket offers: remodeling, pools, financial planning, private schools.
- Route H002 — Est. median household income $76,784, 568 homes
- Route H003 — Est. median household income $65,004, 690 homes
- Route H001 — Est. median household income $54,628, 815 homes
- Route C001 — Est. median household income $41,676, 1,589 homes
- Route C003 — Est. median household income $33,869, 399 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.
- Route H001 — Est. families with children under 18 36.9%, 815 homes
- Route H002 — Est. families with children under 18 33.2%, 568 homes
- Route C003 — Est. families with children under 18 31.9%, 399 homes
- Route C001 — Est. families with children under 18 30.4%, 1,589 homes
- Route H003 — Est. families with children under 18 9.2%, 690 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.
- Route H003 — Est. owner-occupied homes 90.5%, 690 homes
- Route H002 — Est. owner-occupied homes 86.3%, 568 homes
- Route H001 — Est. owner-occupied homes 70.9%, 815 homes
- Route C001 — Est. owner-occupied homes 61.9%, 1,589 homes
- Route C003 — Est. owner-occupied homes 50.3%, 399 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.
- Route C003 — Est. residents who moved in the past year 18.8%, 399 homes
- Route H001 — Est. residents who moved in the past year 16.2%, 815 homes
- Route H002 — Est. residents who moved in the past year 15.9%, 568 homes
- Route H003 — Est. residents who moved in the past year 12.2%, 690 homes
- Route C001 — Est. residents who moved in the past year 8.8%, 1,589 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.
- Route H002 — Est. homes built 2010 or later 13.0%, 568 homes
- Route H003 — Est. homes built 2010 or later 11.8%, 690 homes
- Route C001 — Est. homes built 2010 or later 9.5%, 1,589 homes
- Route C003 — Est. homes built 2010 or later 9.4%, 399 homes
- Route H001 — Est. homes built 2010 or later 8.4%, 815 homes
Select these 5 routes on the route map
Most businesses
For B2B offers: office supplies, cleaning, IT, catering and commercial services.
- Route C001 — USPS business mailboxes 203, 1,589 homes
- Route C003 — USPS business mailboxes 37, 399 homes
- Route H002 — USPS business mailboxes 4, 568 homes
- Route H001 — USPS business mailboxes 3, 815 homes
Select these 4 routes on the route map
Every carrier route in 78578
| Route | Type | Homes | Businesses | Est. median income | Est. owners | Est. families with kids | Est. moved in past year |
|---|---|---|---|---|---|---|---|
| C001 | City | 1,589 | 203 | $41,676 | 61.9% | 30.4% | 8.8% |
| C003 | City | 399 | 37 | $33,869 | 50.3% | 31.9% | 18.8% |
| H001 | Highway contract | 815 | 3 | $54,628 | 70.9% | 36.9% | 16.2% |
| H002 | Highway contract | 568 | 4 | $76,784 | 86.3% | 33.2% | 15.9% |
| H003 | Highway contract | 690 | 0 | $65,004 | 90.5% | 9.2% | 12.2% |
Income, owners, families and movers are estimates for each route (how we estimate them); mailbox counts are current USPS figures. Open 78578 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
- 78521 — Brownsville city, TX (6.9 mi)
- 78566 — Brownsville city, TX (8.2 mi)
- 78526 — Brownsville city, TX (9.6 mi)
- 78575 — Brownsville city, TX (15.1 mi)
- 78597 — South Padre Island town, TX (16 mi)
- 78520 — Brownsville city, TX (16.1 mi)
- 78583 — La Tina Ranch CDP, TX (19.6 mi)
- 78586 — San Benito city, TX (21.5 mi)
Areas that include 78578
- Brownsville, TX ZIP codes — 6 ZIP codes
- Port Isabel, TX ZIP codes — 1 ZIP code
- Laguna Vista, TX ZIP codes — 1 ZIP code
- Laguna Heights, TX ZIP codes — 1 ZIP code
- Cameron County ZIP codes — 16 ZIP codes
- Texas ZIP code data
Where it ranks
- No. 3 of 13: highest median home value in Cameron County
- No. 4 of 13: highest share of owner-occupied homes in Cameron County
- No. 3 of 13: highest share of residents who moved in during the past year in Cameron County
- No. 2 of 13: highest median age in Cameron County
Mail every home in 78578
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) 78578, which approximates the USPS ZIP code area. Census figures: American Community Survey 5-year estimates, 2020–2024.
Frequently asked questions
- What city is 78578 in?
- 78578 is a Port Isabel, TX mailing address. By land area, 32% lies inside Brownsville, 12% lies inside Port Isabel and 8% lies inside Laguna Vista; the rest is outside any Census-defined city or community.
- What county is 78578 in?
- 78578 is in Cameron County.
- What is the population of 78578?
- About 10,016 people (±478), according to the Census Bureau's American Community Survey 5-year estimates for 2020–2024. The 2020 Census counted 10,076.
- What is the median household income in 78578?
- $51,880 (±$16,789), 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 78578?
- 5 USPS carrier routes with 4,061 residential and 247 business mailboxes (4,308 in all), from the route data stored by EDDM2GO. An EDDM mailing can target any combination of these routes.
- What ZIP codes are near 78578?
- The closest, measured center to center: 78521 (6.9 mi, Brownsville), 78566 (8.2 mi, Brownsville), 78526 (9.6 mi, Brownsville), 78575 (15.1 mi, Brownsville), 78597 (16 mi, South Padre Island) and 78520 (16.1 mi, Brownsville).
This product uses the Census Bureau Data API but is not endorsed or certified by the Census Bureau.