Envelopes

RAJAPACK UK’s business envelopes keep your correspondence secure and professional, from everyday white envelopes to hard-wearing Manilla and A4 envelopes for larger documents. Our range is designed for office managers, post-room and mailroom teams, and the procurement and finance staff who send letters, invoices, statements and contracts every day. It covers everything you need to package and post business documents cost-effectively, while presenting a professional image to your clients.

Whether you're posting a single A4 envelope with an unfolded report, running a mass mailing of folded letters, or simply restocking the stationery cupboard, we've got you covered. We stock envelopes in every standard mail format, including C4, C5 and DL. Choose from self-seal and peel-and-seal closures, plain or windowed fronts, and a range of paper weights to suit everything from lightweight letters to heavier documents.

Our range covers:

• White business envelopes - the cost-effective cornerstone of any post room, in plain and windowed formats to save on labelling. Includes white self seal envelopes and business envelopes, with peel and seal closure. Available in popular sizes such as C4, C5 and DL.
• Manilla envelopes - economical brown envelopes ideal for mass mailings and for sending paper documents unfolded, including self seal manilla envelopes and manilla gusset envelopes with a peel and seal closure.
• A4 and large envelopes - C4 envelopes and large-format envelopes that hold an unfolded A4 sheet, keeping reports, certificates and brochures flat in the post.
• Letter and DL envelopes - DL and C5 envelopes sized for folded letters, invoices and compliment slips.
• Self-seal and peel and seal envelopes - fast-closing formats for high-volume post rooms, including C5 peel and seal envelopes.

Key features and benefits:

• Present a professional image - clean white and Manilla business envelopes give your letters, invoices and statements a consistent, businesslike finish.
• Send documents unfolded - C4 and A4 envelopes hold an unfolded A4 sheet, so reports, certificates and contracts arrive flat and crease-free.
• Save on labelling - windowed white envelopes show the address printed on the document itself, cutting label costs on high-volume mailings.
• Seal quickly at volume - self-seal and peel and seal closures let post-room teams pack and despatch faster than gummed alternatives.
• Match the envelope to the job - a full range of standard sizes, from DL for folded letters to C4 for unfolded A4, means the right fit for every document.
• Choose recyclable paper stock - paper-based white and Manilla envelopes are widely recyclable at kerbside with your other paper and cardboard.

Choosing the right envelope size:

When selecting business envelopes for your post room, consider:

• Document size and folding - match the envelope to how the document travels. An unfolded A4 sheet needs a C4 envelope (229 x 324mm); A4 folded once fits a C5 (162 x 229mm); A4 folded into thirds fits a DL (220 x 110mm).
• Weight and contents - heavier documents and multi-page mailings benefit from a heavier paper weight to resist tearing in transit.
• Closure type - self-seal and peel and seal closures speed up high-volume packing, and both remove the need to moisten a gummed flap.
• Window or plain - windowed envelopes save on address labels where the document already shows the recipient address; plain envelopes suit hand-addressing or label printing.
• Volume and cost - for regular mass mailings, larger pack quantities bring the cost per unit down.

Examples include:

• C4 and A4 envelopes are ideal for posting unfolded reports, certificates and brochures.
• C5 envelopes suit A4 documents folded once, such as invoices and statements.
• DL envelopes are the standard choice for letters and compliment slips folded into thirds.
• Manilla envelopes are the economical option for high-volume paper mailings.

If you're posting more than paperwork, choose the right format for the contents. For documents that can't be folded or bent, our cardboard envelopes add rigidity. For fragile or high-value items that need cushioning, our Jiffy bags give added protection, while mailing bags are ideal for clothing items. And for rolled items such as posters and plans, postal tubes keep them crease-free.

FAQs

What size is an A4 envelope?

An A4 envelope is one sized to hold an unfolded A4 sheet (210 x 297mm). In standard envelope sizing this is a C4 envelope, which measures 229 x 324mm and leaves room for the sheet plus a little clearance. C4 and A4 envelopes are used for reports, certificates and documents that must not be folded.

What is the difference between C4, C5 and DL envelopes?

The C-series sizes relate to how an A4 sheet is folded. A C4 (229 x 324mm) holds an unfolded A4 sheet; a C5 (162 x 229mm) holds A4 folded once, or an A5 sheet; and a DL (110 x 220mm) holds A4 folded into thirds, which is the usual format for business letters and compliment slips.

What is a Manilla envelope?

A Manilla envelope is a business envelope made from strong buff-brown paper, traditionally used for sending documents without the need to fold them. Manilla envelopes are usually more economical than white envelopes and are well suited to high volume mass mailings where a premium white finish isn’t required.

What is the difference between self-seal and peel and seal envelopes?

Self-seal envelopes close by pressing two latex-coated strips together, while peel and seal envelopes have a protective strip you remove to expose an adhesive line before sealing. Both close without moisture and are quicker than traditional gummed envelopes, which makes them popular in busy post rooms.

Are business envelopes recyclable?

Plain paper white and Manilla envelopes are widely recyclable at kerbside with paper and cardboard. Envelopes with plastic windows can usually still be recycled, as most UK paper mills separate the film during processing, though removing the window first is the safest option if your local scheme requires it.

Can I buy envelopes in bulk?

Yes. RAJAPACK UK supplies white envelopes, Manilla envelopes and A4 envelopes to businesses across the UK in bulk, with volume discounts and next-day delivery on orders placed before the daily cut-off. For any enquiries or bespoke requirements, contact the RAJAPACK team for a quote.

Keep your business correspondence professional with RAJAPACK UK

Stock your post room with durable, professional business envelopes from RAJAPACK UK. From everyday white envelopes and Manilla envelopes to C4 and A4 envelopes for unfolded documents, we supply the right format, size and closure for every mailing. Browse the full envelopes & mailing bags range, or contact our packaging experts so they can help you match the right envelope size, weight and closure to your mailings.