UPS recently ended a contract with the United States Postal Service and delivery changes are coming to some post office box users as a result.

U.S. Postal Service (USPS) workers will no longer deliver UPS SurePost packages after the government agency's contract with the parcel service expired this year. The International Brotherhood of Teamsters, a union representing UPS delivery drivers, confirmed the negotiated service agreement's expiration in a Facebook post last week.

UPS SurePost packages will be delivered by UPS drivers only after a contract between UPS and USPS expired this year.

Under the change, UPS Sure Post packages are now only being delivered by UPS drivers, a spokesperson for the International Brotherhood of Teamsters spokesperson told Supply Chain Dive. In the past, the final leg of these deliveries was made by the U.S. Postal Service; now, they will be handled by UPS after the Jan. 1 contract expiration.

United Parcel Service (UPS) is set to implement significant changes to its SurePost service, which has long relied on the United States Postal Service (USPS) for final-mile deliveries, following the expiration of their recent contract,

A few delivery services might be the blame. According to a report, an expire contract agreement between UPS and the US Postal Service has delayed millions of packages across the country.

UPS ends its SurePost agreement with USPS, shifting package deliveries back to UPS drivers and changing delivery processes.