Delivery Services

The USPS offers several levels of service. You choose the service based on how quickly you want the letter or package delivered and how much you're willing to pay. The terminology is sometimes confusing, so we've broken it down below. (Note that there are many additional options within each of these categories, and business mail has even more choices.)

postman anthrax
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New York City postal worker Steven Cimbolic with the Cipro pills the USPS gave him during the anthrax scare in 2001.

Express MailŪ service offers quick delivery for letters, large or thick envelopes, tubes and packages. It includes insurance up to $100 and guarantees overnight or two-day delivery. You can also purchase additional insurance up to $5,000.

Priority MailŪ service offers two- to three-day service to most domestic destinations.

Both Express Mail and Priority Mail have a weight limit of 70 pounds and a maximum length of 108 inches.

First-Class MailŪ service doesn't guarantee delivery within a specific time period, although the typical delivery time is one to three days. It is most often used for personal and business correspondence and bills, but you can also send packages weighing up to 13 ounces.

The Parcel PostŪ service is listed as an "affordable and reliable" option for mailing both large and small packages. Parcel Post rates are based on weight, mailing distance and shape. Packages are typically delivered within two to nine days -- they can weigh up to 70 pounds and measure up to 130 inches in combined length and distance around the thickest part.

­Media MailŪ (also called Book Rate) can be the least expensive way to mail packages and thick envelopes. According to the USPS Web site, contents are limited to books, manuscripts, sound recordings, recorded videotapes and ­computer-readable media (not blank). Packages are usually delivered within two to nine days. Cost is based only on weight, so packages going great distances that cost more with Parcel Post might be cheaper with Media Mail. Media Mail cannot contain advertising, except for incidental announcements in books.