Your Go-To Guide for Envelope Types, Sizes, and Uses

Envelopes are an essential part of everyday communication, whether for business, personal correspondence, invitations, or special occasions. With a variety of sizes, styles, and materials available, choosing the right envelope for your needs is important. In this guide, we explore different types of envelopes, their sizes, and their specific uses.

C-series envelopes are commonly used for documents and correspond with A-series paper sizes.

• C6 Envelope (114mm x 162mm) – Compact and versatile, the C6 envelopes is perfect for A6-sized cards or A4 sheets folded twice. It’s a popular choice for greeting cards, invitations, thank-you notes, and personal correspondence. Customers appreciate its high-quality design, ideal for adding a personal touch to any message. 
• C5 Envelope (162mm x 229mm) – Designed to fit A5 sheets or A4 documents folded once, the C5 envelopes are a reliable option for business correspondence, promotional materials, and small brochures. Known for its durability and polished look, it’s perfect for professional and practical use. 
• C4 Envelope (229mm x 324mm) – The C4 envelopes offer a secure fit for A4 documents without folding, making it ideal for official paperwork, reports, certificates, and legal documents. Its sturdy construction ensures documents arrive flat and uncreased, providing peace of mind for important deliveries. 

DL envelopes are widely used for business letters and fit A4 paper folded into thirds. They are a standard choice for professional correspondence and direct mail campaigns.

Square envelopes come in various sizes and add a unique touch to invitations and greeting cards. Their symmetrical shape is often used for special occasions such as weddings, birthdays, and corporate events.

Custom-printed envelopes can be tailored to include branding, logos, and designs, making them perfect for businesses and marketing campaigns. They can also be used for personalised invitations or event promotions.

• Window Envelopes – Feature a transparent section to display the recipient’s address, commonly used for invoices, bills, and statements.
• Self-Seal and Peel & Seal Envelopes – Convenient options that eliminate the need for licking or moistening glue strips.
• Security Envelopes – Often include opaque interiors to protect confidential information, ideal for legal and financial documents.

• Coloured Envelopes – Available in vibrant hues to match different themes and events.
• Textured and Metallic Envelopes – Add elegance to wedding invitations and special occasion cards.
• Luxury and Handmade Envelopes – Crafted from premium paper stocks, suitable for upscale events and exclusive invitations.

• Gift Card Envelopes – Designed to hold gift vouchers, cash, or small notes.
• Christmas Envelopes – Festive-themed envelopes perfect for holiday greetings and seasonal mail.
• Birthday and Event Envelopes – Customisable with prints and designs to complement party themes.

• Padded or Bubble Envelopes – Offer cushioning for fragile items such as CDs, jewellery, or small electronics.
• Board-Backed Envelopes – Reinforced with stiff cardboard to protect important documents, photos, and artwork.
• Gusset Envelopes – Expandable envelopes that accommodate bulkier items like catalogues and thick booklets.

When selecting an envelope, consider the following factors:

• Size Compatibility – Ensure the envelope size matches your content without unnecessary folds.
• Material and Thickness – High-quality paper enhances durability and presentation.
• Closure Type – Self-seal, gummed, and peel & seal closures offer different levels of convenience.

Colour and Design – Customisation options can enhance branding or add a personal touch.

Envelopes serve a wide range of purposes, from professional correspondence to creative invitations and secure packaging. By understanding the different types, sizes, and features, you can choose the right envelope to enhance your message and make a lasting impression.