The cheapest way to mail with delivery confirmation, if your parcel weighs less than four pounds, is by using first-class mail. If the parcel is within a few ounces of four pounds, priority mail is cheaper and faster than first class. Four priority-mail packages are available with fixed rates for shipments in the United States, to Canada, Mexico or internationally. There is no international delivery confirmation.

Consider first-class or priority mail.

Delivery confirmation is only available on priority mail letters, first-class parcels and priority-mail packages. Priority mail delivery confirmation is $.70 as of 2010. First-class delivery confirmation is $.80 as of 2010. The delivery confirmation records the day the package was shipped with the address of the shipping location. The delivery confirmation also records the date and time of the delivery.

Choose a package.

Assemble the articles you intend to mail and decide which size box or envelope to use. Place the items in the box and fill the box to ensure that the contents will not slide. Address the package.

Weigh the Package.

Weigh the package. If the package weighs less than four pounds, send it first-class mail with $.80 delivery confirmation.

Choose a Priority Mail Package to mail within the United States.

If the package weighs four pounds or more, send it priority mail with $.70 delivery confirmation. Postage for a priority-mail envelope for a letter costs $4.90. A small priority-mail box costs $4.95 to mail. Postage for a medium priority-mail box is $10.70. Postage for a large priority-mail box is $14.50 within the United States. Rates are current as of 2010.