41,704 ZIP Codes

ZIP Codes range from 00501, belonging to the Internal Revenue Service in Holtsville, NY, to 99950 in Ketchikan, AK. Easiest to remember? How about 12345, a unique ZIP Code for General Electric in Schenectady, NY.

Quick! What’s that ZIP Code?

The ZIP Code was introduced in 1963. The first number represents a general geographic area of the nation, “0” in the East moving to “9” in the West. The next two numbers indicate regional areas and the final two, specific Post Offices or postal zones in larger cities. Make it a ZIP+4 Code, introduced in 1983, and mail can be sorted to specific streets, buildings, houses and businesses. Today, ZIP Codes are important parts of the nation’s 911 emergency system. ZIP = Zone or Zoning Improvement Plan.