Envelopes come in a variety of sizes and colors.
Select from the following options:

Standard Business
Widely used for business and personal correspondence.

	No.	Size
	6 1/4	3 1/2 x 6
	6 3/4	3 5/8 x 6 1/2
	7	3 3/4 x 6 3/4
	7 3/4 (Monarch)	3 7/8 x 7 1/2
	Check	3 5/8 x 8 5/8
	9	3 7/8 x 8 7/8
	10	4 1/8 x 9 1/2
	11	4 1/2 x 10 3/8
	12	4 3/4 x 11
	14	5 x 11 1/2

Booklet
For use with booklets, folders, and other types of direct mail.

	No.	Size
	3	4 3/4 x 6 1/2
	4 1/2	5 1/2 x 7 1/2
	5	5 1/2 x 8 1/2
	6	5 3/4 x 8 7/8
	6 1/2	6 x 9
	6 3/4	6 1/2 x 9 1/2
	7 1/4	7 x 10
	7 1/2	7 1/2 x 10 1/2
	9	8 3/4 x 11 1/2
	9 1/2	9 x 12
	10	9 1/2 x 12 5/8
	13	10 x 13

Catalog
Open-end style. Wide seams with heavy gummed flaps provide good protection for mail handling of catalogs, magazines, reports, etc.

	No.	Size
	1	6 x 9
	1 3/4	6 1/2 x 9 1/2
	3	7 x 10
	6	7 1/2 x 10 1/2
	9 3/4	8 3/4 x 11 1/4
	10 1/2	9 x 12
	12 1/2	9 1/2 x 12 1/2
	13 1/2	10 x 13
	14 1/2	11 1/2 x 14 1/2
	15 1/2	12 x 15 1/2

Announcement

	No.	Size
	A-2	4 3/8 x 5 5/8
	A-6	4 3/4 x 6 1/2
	A-7	5 1/4 x 7 1/4
	A-8	5 1/2 x 8 1/8
	A-10	6 1/4 x 9 5/8
	Slimline	3 7/8 x 8 7/8

Baronial
Formal envelopes with deep pointed flap. Widely used for invitations, announcements, and greeting and social cards.

	No.	Size
	4	3 5/8 x 4 5/8
	5	4 1/8 x 5 1/8
	5 1/2	4 3/8 x 5 3/4
	6	4 3/4 x 6 1/2

Single Window Envelopes
Nearly each envelope type and size may have a window. The most common (and recommended by USPS) window size is 1 1/8 x 4 1/2, and the position 7/8 in from left and 1/2 (often 5/8) in from bottom.

Double Window Envelopes
Such envelopes are often used for checks and invoices. The three most popular envelope sizes with double windows are #10. #9 and check.