How long will a letter take?

Enter the ZIP code you're mailing from and the one it's going to. You'll see how many delivery days USPS gives a First Class letter between them, and the day to expect it, counted out on the calendar.

Leave the date as today, or pick the day you mailed it to see when it should arrive.

Want to watch it get there?

This tool tells you when a letter should arrive. PigeonTrail shows you where it is on the way: it prints a USPS barcode on envelopes you stamp yourself, puts every USPS scan on a map, and warns you when a letter falls behind the day USPS expects it.

See how it worksCheck a mailer's postage
The tracking page a buyer sees for a letter from Austin to Columbus, with the day USPS expects it and the route on a map.

Questions about letter delivery times

Updated October 19, 2026. The days come from the USPS Service Standards API for First Class Mail letters, and the calendar skips Sundays and the 11 federal holidays USPS observes.

How long does First Class Mail take?

USPS gives a First Class letter between 1 and 5 delivery days, depending on how far apart the two ZIP codes are and how mail travels between them. The tool above shows the exact number for any pair, from USPS's own service standards.

How does USPS count the days?

The count starts on the day USPS accepts the letter, which for a letter in a collection box is the day it is picked up. Each day after that on which USPS delivers counts once, which means Monday through Saturday, never Sunday, and not on the 11 federal holidays USPS observes. A letter mailed on a Sunday or a holiday starts counting on the next delivery day.

What are USPS service standards?

They are the number of days USPS sets itself as the target for each mail class between every pair of 3 digit ZIP areas, the first three digits of a ZIP code. USPS publishes them through its Service Standards API, which is where these numbers come from.

Is the expected day a guarantee?

No. A service standard is USPS's target for First Class Mail, and First Class Mail has no delivery guarantee. Most letters arrive by the expected day, and some arrive a day or more after it.

Why did my letter take longer?

The usual reasons are ordinary ones:

  • It went into the box after the last pickup, so USPS accepted it the next day.
  • A Sunday or a holiday fell in between, which this tool already counts.
  • It was nonmachinable, too stiff, square or lumpy for the sorting machines, so it was sorted by hand. The letter checker tells you if yours is.
  • The address or ZIP code was wrong or hard to read, so it was sent back to be sorted again.
  • It was short on postage and went back to the sender.
  • Mail volume around December, and storms, slow parts of the network for days at a time.

Can I see where my letter is right now?

Only if it carries a USPS Intelligent Mail barcode, since a stamped letter has no tracking number of its own. PigeonTrail prints that barcode on envelopes you stamp yourself and shows every USPS scan on a map. Our guide Can you track a letter? explains the options.