This is the active USPS Post Office in downtown Christiansted, not to be confused with the Old Post Office, which is closer to Fort Christiansvaern and is a delightful part of the National Park Service's offerings.
PLEASE NOTE (as you will read in most of the visitor's guides to St. Croix) that when entering a business establishment of any kind on St. Croix, and in particular a government office, you should (A) be dressed appropriately (shirt that covers the shoulders and cleavage, shorts or other bottom covering over the bathing suit) and (B) do not start your business transaction or make a request without first acknowledging the other person with a "Good Morning/Afternoon." The level of service and warmth you will receive is proportional to the small nod of respect for the local culture that following these two simple guidelines will mete.
The Christiansted downtown Post Office is, like the other post offices on St. Croix, accessible, convenient, fast, and friendly. Use a flat rate box for domestic mail and stuff it full! USPS rates have gone up in recent years, so if you have more than a box or two of bulky stuff you may be better off buying an extra suitcase and checking it through with the airline.
Unfortunately the lobby is not open on Saturdays (schedules subject to change) and there is no postage vending machine available. So stop in and get your stamps and a smile in person during the week! There is a USPS Mobile app available online from the USPS that you can use to check current retail hours, or go to their website.
If you have a lot of stuff to mail, a rental car, and want easier parking, try the Richmond Hill Post Office just west of Christiansted, about a block west of the traffic light, on the north side of Rt. 75 (North Shore Road). They do have Saturday morning lobby hours (subject to change).
Don't forget the two simple Crucian cultural 'guidelines' above, wherever you go on the island, and you'll find smiles and help and doors opening for you!
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