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Side Opening Envelopes  (3 Products)
Side opening envelopes are suitable for both business and personal mailing because they are available in multiple convenient sizes and are easy to use. Gummed seal envelopes are secure options that help prevent mail tampering, and they are sealable by hand, which makes them suitable for both home and business use. Use booklet envelopes that support machine sealing when sending mail in bulk. Read More
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Quill 6x9 Heavy-duty Booklet Envelope
$42.99 Box
When you buy 5+
Item # 901-BE6924
Lifetime Warranty
Quill Side-Opening Envelopes

Quill Brand® Side Opening Envelopes; 10x15", Brown-Kraft, Ungummed, 40lb., 100/Box

Side-opening envelopes are ideal for holding pamphlets, booklets or flat documents
Deep wide flap secures documents
Made of 40-lb. brown kraft with sturdy side-seam construction
$76.99 Box
When you buy 5+
Item # 901-UG1015OS
Lifetime Warranty
Quality Park® Side Opening Envelopes, 9x12, Gummed, White, 28lb., 250/Box

Quality Park® Side Opening Envelopes, 9x12", Gummed, White, 28lb., 250/Box

Perfect for printing with corporate address and logo
Envelopes open on the long side for easy insertion
Made of white, heavy-duty stock with strong side seams
$52.49 Box
When you buy 5+
Item # 901-37682Q
Quick Ship: 1-2 business day delivery
Want to know more about Side Opening Envelopes

Robust and secure gummed seal envelopes

Gummed seal envelopes made of thick, tough material such as 28-pound paper protects contents such as booklets and heavy files. The security tint feature is useful when sending high-value or confidential correspondence and checks. It creates an opaque shield so that the contents of the mail remain hidden until the recipient opens the envelope. Document envelopes feature paper or plastic construction with snaps or string closures. They are available in clear, translucent, and opaque options. Others include gussets to accommodate more files or documents.

Side-opening envelopes in various sizes

Booklet envelopes are available in sizes small enough for sending invitations as well as large enough to send booklets and magazines. Popular sizes include A1, suitable for RSVPs, cards, and announcements to A10, which are fitting for invitations. Other sizes include from #1 to #14, in addition to other dimensions to cover a wide variety of paper sizes.

These pieces of stationery also come in various shapes and pack sizes including square envelopes. Some can serve as specialty envelopes with their attractive lined interiors to add style to invitations and congratulatory messages, or to show recipients that they are special with unique contents. Environmentally friendly options contain post-consumer material and are themselves recyclable. Brands to choose from include:

  • JAM Paper®
  • LUX Paper™
  • Partners Brand
  • Quality Park™
  • Quill Brand®

Sealing options for paper envelopes

Envelopes come with various sealing mechanisms including gum seals, which are easy to apply by moistening the flap then closing the envelope. Self-seal options have latex strips that protect a gummed layer. The envelopes self seal with a little pressure after removing the strips. Some options also support machine-sealing and these are suitable when sending out mass correspondence. The envelopes come in many colors for both formal and casual communications.

Some choices include display windows that allow users to print mailing information on the letters rather than on both the correspondence and the envelopes. This feature helps reduce work. Find other types of stationery and envelopes such as cash and coin envelopes at Quill.