Important mailing dates to keep in mind: December 20, for letters and cards. Your packages can go out through December 21, but if you wait after that, you'll pay for premium services to get your presents out to your loved ones.

It's the most wonderful time of the year- and the busiest for the post office.

That's why the US Postal Service is extending hours at some local offices.

The locations in Irondequoit, Webster, Rochester, and Westgate will stay open until 4 p.m.

The main Rochester office will be open on Sundays from 9 a.m. to 3 p.m.

USPS spokesperson Karen Mazurkiewicz had advice as to when people should get their letters and cards out:

"You want to get your letters and cards in the mail by December 20th. Your packages can go out December 21st. And if you're going to wait until the last minute, we do have a premium service for priority express mail. December 23rd is the deadline. It's going to be a little more costly, but it is still an option."

The post office suggests that it is always best to mail early, since weather can interfere with your packages being delivered. They also suggest avoiding the office for the next two Mondays, since they are expected to be very busy.