The holiday originated in 1919, on the first anniversary of the 1918 armistice that ended World War I. The annual holiday was previously known as Armistice Day.

As it is a federal holiday, many services, including businesses, government offices and public institutions, are closed.

If you were waiting on mail that was due to be delivered on November 11, don’t necessarily count on it. These postal services are affected on Veterans Day.

United States Postal Service (USPS)

On Veterans Day, there will be no United States Postal Service (USPS) pickup or delivery services. USPS branches will also be closed.

However, you are still able to prepare your post online if you have a USPS.com account, where you can purchase stamps, order boxes, print shipping labels and schedule package collections.

If you are planning to send a letter and small package, mailboxes will remain accessible across the country, so you can drop off post and then it will be ready for pickup when delivery and collections resume on November 12.

Stamps are also sold at most major supermarkets, many of which are open on Veterans Day.

Although there will be no regular mail delivery, Priority Mail Express—which operates 365 days a year—will deliver on Veterans Day.

USPS branches are also closed during the following federal holidays:

New Year’s Day (Jan 1)Martin Luther King Jr. Day (Jan 17)Memorial Day (May 30)Juneteenth (June 20)Independence Day (July 4)Labor Day (September 5)Columbus Day (October 10)Thanksgiving (November 24)Christmas (Monday, December 26 as December 25 falls on a Sunday this year)

UPS

UPS will be running as normal on November 11, including UPS Domestic Ground, Air & International, UPS stores, UPS Forwarding and UPS Express Critical, which operates 24 hours a day, 365 days a year, per its website.

A full UPS holiday schedule can be viewed on the courier’s website here.

FedEx

Most FedEx services will run a normal service on Veterans Day, including FedEx Express, FedEx Ground, FedEx Home and FedEx Freight.

FedEx Custom Critical will be running on November 11 too, as it operates 24 hours a day, 365 days a year.

The only FedEx service that will be operating a modified service on Veterans Day is FedEx Ground Economy, the cheaper shipping option for small and medium businesses.

See the courier’s website for more information on its services for all holidays.