North Bend Post Office, the post office serving North Bend, Nebraska.

Main post office for North Platte, located on Industrial Avenue after moving from downtown.

The O'Neill Post Office building was built in 1936 and 1937, has a 1938 New Deal mural by Eugene Trentham, Baling Hay in Holt County in the Early Days, and was listed on the National Register of Historic Places in 1992.

Oakland Post Office, the post office serving Oakland, Nebraska.

Oconto Post Office, the post office serving Oconto, Nebraska.

Odessa Post Office, the post office serving Odessa, Nebraska.

The Ogallala Post Office at 301 North Spruce Street was built in 1937 and 1938 and has a New Deal mural by Frank Mechau of a cowboy and longhorns.

Olde Towne Post Office, the post office serving Bellevue, Nebraska.

The Orchard Post Office provides US Postal Service mail delivery, P.O. box rental, and postal services for Orchard and surrounding rural Antelope County at ZIP code 68764.

A USDA Service Center in Ord, Nebraska, housing the Farm Service Agency (FSA) and Natural Resources Conservation Service (NRCS).