Envelopes come in so many shapes and sizes that it’s easy to feel overwhelmed, especially when you’re trying to keep postage costs low. If you’ve ever asked, “What size is a standard business envelope?”, “How big is a business envelope?”, or “What size is a business size envelope?”, you’ve landed on the right blog. Grab a cup of coffee (or tea) and let’s dive into it! 

Why Envelope Size Matters  

• First impressions count: Sending your business documents in an envelope that’s too large could feel like delivering a postcard in a pizza box. On the other hand, cramming your paper into an envelope that’s too small is just as bad. 

• Saving on postage: No one wants a surprise bill for “oversized mail.” By choosing the correct envelope size, you avoid extra fees. 

• Document protection: A well-fitted envelope ensures your letters stay wrinkle-free. 

Smith Packaging are proud to support businesses of every size across the UK, with the best business stationery and envelopes. Crafted from PEFC-certified paper, our range of business envelopes spans multiple industry-standard sizes, ensuring you always have the perfect fit. We also offer self-seal and gummed options to guarantee your letters stay securely sealed until they reach the right hands – keeping communication easy and safe.  

The 3 Main Business Envelope Sizes 

While there are many types of envelopes to choose from, the three you’ll encounter most often for business are: DL, C5, and C4. 

DL (Standard Business Envelope) 

• Dimensions (mm): 110 × 220 

• Dimensions (inches): 4.33 × 8.66 

• Perfect For: Tri-folded A4 documents, letters, invoices, and anything that screams “official business.” 

C5 

• Dimensions (mm): 162 × 229 

• Dimensions (inches): 6.38 × 9.02 

• Perfect For: A4 documents folded once, brochures, or marketing materials. 

C4 

• Dimensions (mm): 229 × 324 

• Dimensions (inches): 9.02 × 12.76 

• Perfect For: Full-size A4 documents (no folding required), legal forms, or presentations you want to keep nice and crisp. 

Handy Envelope Reference Chart 

Feel free to print and pin this chart to your corkboard or screenshot it for quick reference.  

Choosing the Perfect Envelope 

1. Measure Your Cargo 

Ask yourself: “Do I want one fold, two folds, or zero folds?” That’s the envelope dilemma in a nutshell. 

1. Double-Check Postage Rules 

Keep your local postal service guidelines bookmarked. An extra inch can mean extra fees. 

1. Order in Bulk 

You never want to run out of envelopes right before sending an invoice or that must-read newsletter. Bulk ordering at Smith Packaging can save you money and a meltdown. 

Sealing the Deal 

Choosing the right size business envelope will keep your documents safe and save you from annoying postage surprises. Do you need business envelopes? Smith Packaging provides high-quality packaging supplies to make mailing straightforward. Have a look at our extensive range of packaging materials here. 

FAQs  

What size is a standard business envelope? 

The standard business size envelope is usually DL, measuring 110 × 220 mm. It comfortably fits an A4 sheet folded into thirds. 

How big is a business envelope? 

Business envelopes typically refers to the DL size, but C5 and C4 can also be used in professional settings, especially if you’re feeling fancy. 

What size is a business size envelope? 

Again, DL (110 × 220 mm) is the usual suspect. But hey, if you need fewer folds or zero folds, C5 or C4 might be your new best friend.