Large Envelope
Dimension Minimum* Maximum
Height 6-1/8 inches (15.557 cm) 12 inches (30.480 cm)
Length 11-1/2 inches (29.210 cm) 15 inches (38.100 cm)
Thickness 1/4 inch (0.635 cm) 3/4 inch (1.905 cm)

* Large envelopes exceed at least one of these dimensions.

For example, an envelope 10 inches long x 8 inches high x 1/4 inch thick
(25.400 cm x 20.320 cm x 0.635 cm) is considered a large envelope because it exceeds the minimum height dimension.

Large envelopes that are rigid, nonrectangular, or not uniformly thick pay package prices.

For large envelopes, length is the longest dimension.

For larger items, see package prices.