REDDING, Calif. -

The clock is definitely running out for those of us who need to get those gifts in the mail.

Today is expected to be the busiest shipping day of the year for all mail carriers. 

According to UPS nearly 34 million packages will be picked up worldwide.

That is double the normal volume.

Here are the dates you need to know to  make sure that those gifts arrive right in time for Christmas.

If you’re using FedEx:

The last day to mail by ground is Tuesday the 17th.

For two day: Saturday the 21st.

For overnight: Monday the 23rd.

For the USPS:

First class mail : Friday the 20th

Priority mail: Saturday the 21st.

Priority mail express: Monday the 23rd.

For UPS:

2nd day air : Friday the 20th.

Next day air: Monday the 23rd.

All carriers said to remember that the longer the wait, the more expensive the shipping will be.

UPS alone expects to deliver more than 129 million packages the week before Christmas, that’s about 300 packages per second.