what is the cheapest way to mail a package depends on the size, weight, and destination of the package. For smaller, lightweight packages, USPS First-Class Mail is often the most affordable option. For slightly larger items, USPS Priority Mail Flat Rate boxes offer a fixed price regardless of weight or destination. For international shipments, services like ePacket (for items from China) or USPS First-Class Package International are affordable choices. It’s essential to compare rates from different carriers, such as UPS and FedEx, to find the most cost-effective solution for specific shipping needs, taking into account delivery times and tracking capabilities.