The United States Postal Service, often abbreviated as USPS, is an agency which provides postal service in the US. Modern two-letter abbreviated codes for the states were adopted by USPS in 1963. Most of them have never been changed since then. Nebraska's code was changed from "NB" to "NE" in 1969.

United States Postal Service 2 letter code for the state of Maine is ME, the state of Massachusetts is MA, the state of Michigan is MI, and the state of Minnesota is MN.

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