Class of Mail

Weight

Speed

Free Forwarding

and Return

Special

Services 

Presort

Discounts

Express Mail

70 lbs or less

1-2 Days

Yes

Yes

No

Priority Mail

70 lbs or less

1-3 Days

Yes

Yes

No

First-Class Mail – Letters

3.5 oz or less

1-3 Days

Yes

Yes

Yes

First-Class Mail – Flats

13 oz or less

1-3 Days

Yes

Yes

Yes

First-Class Mail – Parcels

13 oz or less

1-3 Days

Yes

Yes

Yes

Standard Mail

70 lbs or less

2-8 Days

No

Parcels Only

Yes

Package Services

70 lbs or less

2-8 Days

No

Yes

Yes