Large Flat Rate Boxes. From $71.05 at Post Office. From $67.50 for Commercial Base. From $67.50 for Commercial Plus. First-Class Mail International ® Letters and postcards from $1.20 for all countries. Large Envelopes (Flats) from $2.40 for all countries. First-Class Package International Service ® From $14.25 at the Post Office. First-Class Mail ® is an affordable mail service for standard-sized, single-piece envelopes weighing up to 3.5 oz and large envelopes and small packages weighing up to 13 oz with delivery in 3 business days or less. From $0.55 at a Post Office. Holds parcels up to 25'x 9.5'x 23' (or two 11.75 x 11 x 23 parcels on either side of center post) Capacity: 29 gallons/4.0 cubic feet. A Porch Box® parcel box is.

Sizes for Parcels


If your mailpiece isn't a postcard, Letter, or a flat (large envelope) , then it's a parcel. You may be surprised to find out that 'parcels' are not just big boxes. Many mailers send small parcels in all classes of mail. Parcels offer some of the best value for your postage dollars.

Parcel Dimensions
Generally, commercial parcels must measure:
- At least 3 inches high x 6 inches long x 1/4 inch thick.
- Except for USPS Retail Ground and Parcel Select, no mailpiece may measure more than 108 inches in length and girth combined. Length is the measurement of the longest dimension and girth is the distance around the thickest part (perpendicular to the length). Maximum weight is 70 pounds.
Machinable Parcels
If you prepare your parcels so that they can be processed on Postal Service equipment, your parcel is considered 'machinable.' Machinable parcels are easier to process and deliver, so they are less expensive to mail. Machinable parcels must measure:
Mailbox Parcel Box
- No more than 27 inches long x 17 inches width x 17 inches high.
- No more than 25 pounds (35 pounds for Parcel Select and Parcel Return Service, except books and other printed matter which cannot exceed 25 pounds).
See Full List On Royalmail.com
Balloon and Oversized Prices for Parcels
Some parcels may be subject to specialized prices. USPS Retail Ground packages that are large but very light (less than 20 pounds) are charged the postage for a 20 pound package. This is often referred to as a balloon price. Very large USPS Retail Ground or Parcel Select packages (over 108 inches but not more than 130 inches in combined length and girth) are charged an oversized price.
