The United States Postal Service (USPS) is giving Americans a holiday heads-up: Ship your packages by these dates if you want them to arrive in time for Christmas. 
  • USPS Retail Ground® Service — Dec. 17
  • First-Class Mail® Service — Dec. 17
  • Priority Mail® Service — Dec. 19
  • Priority Mail Express® Service — Dec. 23
Because Christmas falls on a Sunday this year, the deadlines are one day earlier than in 2021. This also means USPS won't be delivering on the Monday after the holiday. 
These are recommended deadlines, of course, not a guarantee of timely delivery. The agency still has its work cut out for it through the rest of the year, and earlier is always better. Otherwise you might be paying some extra fees for expedited deliveries. 
"Customer traffic at all Post Office locations has been steadily increasing since Dec. 5, and this week is expected to be the busiest," the agency said in a news release on Monday. "The Postal Service has been preparing for the holiday peak — the time between Black Friday and New Year’s Day — since January, building on investments and organizational strategy improvements made ahead of the successful 2021 holiday mailing and shipping season."
More than 41,000 part-time workers have converted to full-time since the beginning of the year, and an extra 20,000 seasonal workers joined their ranks. The agency also installed 137 new package sorting machines as part of its Delivering for America plan launched in March 2021. 
The 10-year plan aims to stabilize the Postal Service's finances through price hikes and, in some cases, slower delivery service. As part of the plan, USPS also consolidated more than 200 post offices into more concentrated regional hubs earlier this year. 
Other details about USPS's recommended shipping times are available here
Other shipping companies have released their holiday deadlines as well.
UPS
  • UPS® Ground shipping - location dependent 
  • UPS 3 Day Select® - Dec. 20
  • UPS 2nd Day Air® services - Dec. 21
  • UPS Next Day Air® services - Dec. 22
FedEx
  • FedEx Same Day - Dec. 23 
  • FedEx Express Saver - Dec. 20 
  • FedEx 1 Day Freight - Dec. 22
  • FedEx 2 Day Freight - Dec. 21
  • FedEx 3 Day Freight - Dec. 20 
Updated December 16, 2022 at 2:07 p.m. ET to add UPS and FedEx recommended shipping dates.