Does USPS Deliver on Sundays?

Yes, USPS does delivers packages and mails on Sundays, but not all of them. Only the packages that were ordered using Priority Mail Express and some of the Amazon packages are delivered on Sundays. Other than that, USPS doesn’t delivers regular packages on Sundays. So, it is important that you order your package through Priority Mail Express if you want it to be delivered on Sundays.