Gusset Envelopes

More About Gusset Envelopes

Gusset Envelopes for Irish Businesses

Gusset envelopes are designed to hold bulky or thick contents that a standard flat envelope cannot accommodate. The expandable gusset — a folded panel running along the base or sides of the envelope — allows the envelope to open out as needed, making it well suited to thick documents, files, catalogues, brochures, reports, and books that need to be posted without compression or damage. Hunt Office Ireland stocks 21 gusset envelopes across a wide range of sizes, weights, and formats from brands including Q-Connect, New Guardian, 5 Star, Tyvek, Plus Fabric, and E-Green, with 17 of the 21 products carrying eco-friendly credentials. Fast nationwide delivery is available on all orders.

What Is a Gusset Envelope?

A gusset envelope differs from a standard envelope in that it has an expandable section — typically a pleated or folded panel — built into the base or sides. This gusset allows the envelope to expand in depth to accommodate thicker contents while maintaining a secure, flat seal at the flap. Most gusset envelopes in this range feature a 25mm gusset, with some options extending to 38mm, 40mm, 50mm, and 80mm for particularly bulky applications. Because they are designed for heavier loads, gusset envelopes are generally made from heavier paper stock than standard envelopes — weights in this range run from 115gsm through to 130gsm.

Gusset Envelope Sizes

The majority of products in this range are C4 (324x229mm), making them suitable for A4 documents sent flat without folding — the most common use case for gusset envelopes in an office environment. C5 gusset envelopes (162x229mm) are also available for A5 documents or smaller multi-page inserts. For larger applications, the range also includes non-standard sizes spanning from 330x250mm up to 450x350mm, covering requirements such as posting A3-adjacent documents, large catalogues, or oversized reference materials. The full size filter on the Hunt Office website makes it straightforward to locate the right dimensions.

Plain vs Window Gusset Envelopes

Plain gusset envelopes have no window and can be written on, printed on, or used with a franking machine or address label — making them a versatile choice for businesses that address envelopes in different ways depending on the application. Window gusset envelopes display the recipient's address through a transparent panel in the front of the envelope, eliminating the need to address each envelope separately and reducing the risk of mismatch between the letter and the envelope. Window gusset options are available in both manilla and white from 5 Star, Q-Connect, and Plus Fabric.

Paper Weight: 115gsm, 120gsm, and 130gsm

Gusset envelopes are made from heavier stock than standard envelopes to withstand the additional weight and pressure of bulky contents in transit. The 115gsm options from 5 Star are a solid everyday choice for most office mailing applications. The 120gsm options from Q-Connect and 5 Star offer additional strength for heavier inserts. The 130gsm options from New Guardian — including the New Guardian Armour range with 50mm gussets — are the heaviest-duty products in the range and are suited to the most demanding postal applications, such as posting thick legal files, large catalogues, or heavy reference documents.

Tyvek Gusset Envelopes

Tyvek gusset envelopes are made from a synthetic material that is significantly stronger and more tear-resistant than paper. Manufactured by DuPont, Tyvek is waterproof, puncture-resistant, and extremely lightweight, making it the preferred choice for mailing valuable or irreplaceable documents that need reliable protection in transit. The Tyvek C4 gusset envelopes in this range feature a 38mm gusset and are available in white, in packs of 20 and 100.

Eco-Friendly Gusset Envelopes

17 of the 21 gusset envelopes in this range carry eco-friendly credentials, including options from E-Green — a brand specifically focused on sustainable mailing solutions. The E-Green range includes C5, C4 Plus, and C3 Plus gusset mailers with gussets ranging from 40mm to 80mm, available in packs of 200 and 250. For organisations with sustainability commitments or green procurement requirements, the majority of the range qualifies without compromising on specification.

Why Choose Hunt Office for Gusset Envelopes?

Hunt Office stocks one of the most comprehensive selections of gusset envelopes available from a single Irish office supplies supplier, covering standard and oversized formats, multiple paper weights, plain and window styles, and both everyday and heavy-duty brands. With fast nationwide delivery across Ireland and competitive pricing across the full range, Hunt Office makes it straightforward for businesses of all sizes to source the right gusset envelope for their mailing needs.

Other product categories you may be interested in

• Business Envelopes
• C4 Envelopes (A4)
• C5 Envelopes (A5)
• Cardboard Mailing Boxes
• Post & Packing Supplies