Which ZIP code in Williamson County has the highest median age?

78633 (Georgetown), at 67.3 (±0.8), among 22 ZIP codes with at least 1,000 residents.

Why are some ZIP codes missing?

ZIP codes with fewer than 1,000 residents are left out because their survey estimates swing too much to rank, and so are ZIP codes where the Census Bureau did not publish this figure.

Oldest ZIP codes in Williamson County, TX

These are the 22 ZIP codes in Williamson County with the highest median age, out of 22 with at least 1,000 residents. 78633 (Georgetown, 67.3), 76530 (Granger, 43.3) and 76574 (Taylor, 42.2) lead the list. There is no single "best" ZIP code in Williamson County; the right one depends on who you want to reach, so the same ZIP codes are ranked several ways below.

Oldest ZIP codes in Williamson County

Rank	ZIP	Mailing city	Median age	Residents	Households	Residential mailboxes
1	78633	Georgetown	67.3 ±0.8	29,309	14,245	18,369
2	76530	Granger	43.3 ±10.8	2,598	959	969
3	76574	Taylor	42.2 ±2.6	20,242	7,752	8,408
4	78750	Austin	41.3 ±1.7	29,277	11,875	11,595
5	78628	Georgetown	40.7 ±1.5	50,822	19,084	27,555
6	76511	Bartlett	40.3 ±6.6	2,702	920	859
7	78681	Round Rock	39.3 ±1.1	56,691	20,135	21,501
8	78613	Cedar Park	37.7 ±0.8	89,956	33,919	35,237
9	76578	Thrall	37.6 ±3.6	1,762	571	721
10	78641	Leander	37.0 ±0.7	99,865	35,410	48,032
11	78642	Liberty Hill	36.9 ±2.0	26,434	8,696	14,168
12	76527	Florence	36.9 ±9.9	4,918	1,582	1,897
13	78717	Austin	36.8 ±1.4	37,262	14,939	18,089
14	78621	Elgin	36.2 ±1.6	30,411	10,175	12,832
15	78665	Round Rock	35.5 ±0.8	66,171	24,162	30,636
16	78664	Round Rock	35.1 ±1.3	62,060	23,484	23,993
17	78634	Hutto	34.9 ±1.5	46,413	15,808	21,724
18	78729	Austin	34.9 ±1.2	30,460	14,500	15,015
19	78728	Austin	33.9 ±0.8	26,777	13,169	14,485
20	78626	Georgetown	33.5 ±0.7	48,072	16,813	23,417
21	78615	Coupland	33.2 ±5.2	1,637	549	666
22	76537	Jarrell	31.1 ±2.0	16,272	5,448	10,169

How we ranked them

Ranked by median age of all residents, highest first (ACS 5-year estimates, 2020–2024). ZIP codes need at least 1,000 residents to be ranked; 22 of 24 qualify.

Which of these to mail, and why

Older ZIP codes respond to health care, hearing and vision, Medicare plans, home safety, estate planning and services that come to the door.

The top five ZIP codes on this list hold 53,915 households, on 88 carrier routes with 66,896 residential mailboxes. Open any of them on the route map to see each carrier route's own figures before you choose.

Open 78633 on the EDDM route map

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Businesses that mail these ZIP codes

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Frequently asked questions

Which ZIP code in Williamson County has the highest median age?: 78633 (Georgetown), at 67.3 (±0.8), among 22 ZIP codes with at least 1,000 residents.
How is this ranking calculated?: Ranked by median age of all residents, highest first (ACS 5-year estimates, 2020–2024).
Why are some ZIP codes missing?: ZIP codes with fewer than 1,000 residents are left out because their survey estimates swing too much to rank, and so are ZIP codes where the Census Bureau did not publish this figure.

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