The following is a list of the 70 The Federal Information Processing Standard (FIPS) code, used by the U.S. government to uniquely identify counties, is provided with each entry.

FIPS codes are five-digit numbers; for Pennsylvania the codes start with 42 and are completed with the three-digit county code.

The FIPS code for each county in the table links to census data for the specific county.

[3] The Province of Pennsylvania's Three Lower Counties had been transferred from New York Colony in 1682.

In 1701 these counties became a separate colony called Delaware Colony, although it shared the same colonial governor as Pennsylvania until independence in 1776.