Mills Post Office

526 SW Wyoming Blvd, Mills, WY 82644

Contact Numbers

Phone: 307-235-3500
Fax: 307-234-4569
TTY: 877-889-2457
Toll-Free: 1-800-Ask-USPS® (275-8777)

Retail Hours

Lobby Hours
PO Box Access Available

Monday 24 hours
Tuesday 24 hours
Wednesday 24 hours
Thursday 24 hours
Friday 24 hours
Saturday 24 hours
Sunday 24 hours

Last Collection Times

Monday 5:00pm
Tuesday 5:00pm
Wednesday 5:00pm
Thursday 5:00pm
Friday 5:00pm
Saturday 11:30am
Sunday Closed

Bulk Mail Acceptance Hours

Monday 9:00am - 4:00pm
Tuesday 9:00am - 4:00pm
Wednesday 9:00am - 4:00pm
Thursday 9:00am - 4:00pm
Friday 9:00am - 4:00pm
Saturday Closed
Sunday Closed

*This facility does not process US Passports applications or renewals. Check nearby locations below.

  • Bulk Mail Acceptance
  • Bulk Mail Account Balance
  • Bulk Mail New Permit
  • Burial Flags
  • Business Line
  • Business Reply Mail Account Balance
  • Business Reply Mail New Permit
  • Duck Stamps
  • General Delivery
  • Money Orders (Domestic)
  • Money Orders (Inquiry)
  • Money Orders (International)
  • Pickup Accountable Mail
  • Pickup Hold Mail
  • PO Box Online
  • Lot Parking

Visit our Links Page for Holiday Schedule, Change of Address, Hold Mail/Stop Delivery, PO Box rentals and fees, and Available Jobs.

*Please call to verify information. Is anything incorrect? Let us know here

Nearby Post Offices:

Downtown Casper
150 E B St Lobby
2.1 miles away

411 N Forest Dr
3.9 miles away

236 Texas St
4.3 miles away

22495 State Highway 220
17.9 miles away


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Why don't you have large boxes for which you can leave patrons a key to get packages after hours? Your hours are only convenient for the retired or people who actually get a lunch break. I cannot get to your post office most weekdays when you are open. I work 6 a.m. to 8 p.m. with no lunch break. I want the package. I can cancel my morning appointment and pick it up on Saturday, 11/17/18. Or you can redeliver to my physical address, 1607 CY Avenue, Suite 102, Casper, WY 82604

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