78664 ZIP Code - United States

This ZIP Code belongs to the following areas. Below you can see the map of the postal area.

City	City	ZIP Type	Estimated Population
Round Rock, TX	PRIMARY	STANDARD	42.720
Old Round Rock, TX	NOT ACCEPTABLE	STANDARD	42.720
Three Point, TX	NOT ACCEPTABLE	STANDARD	42.720

Postal Zone from ZIP Code 78664 - United States

County	FIP	Weight
Williamson	48491	88.5%
Travis	48453	11.5%

Check the list of Texas ZIP Code.

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PRIMARY: means an the primary city name. Official city name, although the city name might also have another acceptable name.
ACCEPTABLE: means an adequate city name. City names that are abbreviated will frequently be listed as unacceptable because abbreviations are not an acceptable city name format.
NOT ACCEPTABLE: Means an inadequate city name has been entered or received based on information entered.
UNIQUE: Assigned to a company, government agency, or entity with sufficient mail volume, based on average daily volume of letter size mail received, availability of ZIP Code numbers in the postal area, and the US mail service cost-benefit analysis.