Reduce the list, select first 2 letters of the city:
Listing cities (31 place(s)). Select the City to see the postcode(s):
Listing cities (31 place(s)). Select the City to see the postcode(s):
Position: Postcodes > United States > Texas > O.... >
Postcode finder: United States, List of the cities starting with O. United States Texas Postcodes (Desktop version).