USPS Complaints By Phone: United States Parcel Services or USPS is an American based government-owned courier agency that renders courier services in the United States. USPS is basically liable to handle all the courier related services and deliver the Packages or the mails throughout the United States. You will hardly see any individual or the household which has not to get benefited from the USPS services, or where the USPS has not reached and due to that USPS is known as the US post office. The network of USPS is very extensive and since it is a government-owned body, the USPS is obliged to reach out to every individual or household in any state of the US and deliver their packages. Being the largest government postal body the USPS has constituted a customer service support department, where the customers can call for any kind of query or they can even get their complaints registered for any kind of\u00a0USPS services. As the USPS is obliged to serve the entire United States with its equal postal services, hence if any customer is having any grievance then it is the liability of the USPS to put light on that grievance and sort that out in the customer's favour. If you are having any kind of query or complaint then you can file your complaint by reaching to any of the below options. \tYou can file your complaint by phone calls calling at the 1-800-877-8339 USPS phone number. \tYou can reach out to the local USPS post office station manager and get your complaint registered there. \tYou can further mail your complaints or write a complaint letter to the USPS postal service consumer advocate. So, you may file or get your complaint registered by following any of the above methods, and USPS will take the required action to sort out the concerning complaints.