With Christmas just weeks away, millions of people are making headway on their holiday shopping lists.

The three largest carriers in the U.S. — The United States Postal Service, UPS and FedEx — released their deadlines for shipping this year to make sure people get their gifts on time.

Here are dates to keep in mind to get gifts by Christmas Day:

USPS

For the lower 48 states:

  • USPS ground advantage service: Dec. 18
  • First-class mail service: Dec. 18
  • Priority mail service: Dec. 19
  • Priority mail express service: Dec. 21

For Alaska and Hawaii:

  • USPS ground advantage service: Dec. 16
  • First-class mail service: Dec. 18
  • Priority mail service: Dec. 19
  • Priority mail express service: Dec. 20

UPS

  • UPS ground: Use this calculator
  • UPS three-day select: Dec. 19
  • UPS second-day air: Dec. 20
  • UPS next-day air: Dec. 23

FedEx

  • FedEx ground economy: Dec. 13
  • FedEx express saver: Dec. 19
  • FedEx 2Day and FedEx 2Day AM: Dec. 20
  • FedEx first overnight, FedEx priority overnight, FedEx standard ovenright: Dec. 23
  • FedEx SameDay: Dec. 24