Time is running out to get those last minute Christmas gifts shipped, and different mail carrier services and online retailers have already announced their cut-off dates for delivery by Dec. 25.

To avoid heightened shipping rates, it is advised that packages be sent by December 12th to the 15th, Seasonal Savings Zone reported.

"Overall, once we get to the Christmas Day holiday, we expect to process and deliver about 470 million packages," Peter Hass, spokesman for the Postal Service's Arizona District, told Trivalley Central.

The Postal Service estimates that it will carry 15 billion pieces of mail from Thanksgiving to Christmas. The Monday before Christmas week is usually the busiest for FedEx, UPS and the Postal Service.

Hass suggested mailing packages earlier instead of waiting until the cut off time not only because of a high volume of packages, but also because of uncontrollable weather.

"Mailing earlier is probably the best of two words I can offer to any postal customer," he said. "This is our season. This is our biggest time of the year."

Here are the package deadlines for U.S. mail carriers:

FedEx

• Fri., December 12: Last day to ship for customers that have a regularly scheduled FedEx SmartPost pickup or who drop off packages to a staffed FedEx location.
• Mon., December 15: Last day to ship using FedEx SmartPost for customers that use a third-party service or drop-ship directly to a FedEx SmartPost hub.
• Wed., December 17: Last day to ship using FedEx Ground if you have a regular scheduled pickup or you drop off shipments at a staffed FedEx location. Last day for FedEx Home Delivery.
• Sat., December 20: Last day to ship using FedEx Express Saver
• Mon., December 22: Last day to ship using  FedEx 2Day and FedEx 2Day A.M.
• Tues., December 23: Last day to ship using FedEx Standard Overnight, FedEx Priority Overnight, and FedEx First Overnight
• Thur., December 25: Last day to ship using FedEx SameDay
• For more information, visit FedEx Holiday Shipping 2014 .

U.S. Postal Service

• Mon., December 15: Last day to ship using standard parcel post
• Sat., December 20: Last day to ship using First Class Mail & Priority Mail
• Tues. December 23: Last day to ship using Priority Mail Express
• Priority Mail Express money-back guarantee is suspended for shipments mailed Dec. 22-25

UPS

• Mon., December 15: Last day to ship using UPS Ground, UPS 3 Day Select
•  Mon., December. 22: Last day to ship using UPS 2nd Day Air
• Tues., December. 23: Last day to ship via UPS Next Day Air
• For more information, visit UPS 2014 Year-End Holiday Schedule

Online stores have also released their holiday deadlines: