What Is a #10 Envelope, Anyway?

What You Need to Know about Business-Sized Envelopes

Flock of birds flying in email envelope formation
A #10 Envelope, Also Known as a "Business-Sized" Envelope. Image (c) Tim Robberts / Getty Images

What's a #10 Envelope? Here Are Their Sizes and Dimensions

If you're not familiar with #10 envelopes right off the cuff, you might know them better as business-sized or standard envelopes. In any case, you would probably recognize their long, thin shape. They have a standard size of 4 1/8 inches high by 9 1/2 inches long.

#10 envelopes are designed to hold a standard 8 1/2 x 11-inch piece of paper folded into three sections, making them ideal for offices.

They are perfect for sending invoices, checks, or other business letters. If you'd like to see a demonstration of the proper way to fold a letter to fit a #10 envelope, check out this YouTube video.

#10 envelopes and letter-sized envelopes are the most commonly used in America. Letter-sized envelopes are narrower and longer than #10s, while #10s are longer and more rectangular.

How to Make Your Own #10 Envelopes:

Need a #10 envelope in a hurry, and don't want to run out to the store? Or maybe you'd like to save money by turning a regular piece of paper into the envelope you need?

As it turns out, you can easily create your own #10 envelope with nothing but a glue stick, a ruler, some scissors, your printer, and this envelope folding tutorial from Instructables.

It might take a little practice to get these right, but if you need an envelope in a pinch, being able to simply make one yourself comes in handy!

Using #10 Envelopes to Enter Sweepstakes:

If you want to enter mail-in sweepstakes, #10 envelopes are one of the essential supplies you'll need to get started. Many sweepstakes specify in their rules that you'll need to send your entries in a standard business-sized envelope to enter.

Be sure to follow the rules carefully, because using the wrong-sized envelope could disqualify you from the sweepstakes and destroy your chance of winning.

Many sweepstakes sponsors will disqualify anyone who deviates from their rules, even slightly.

How to Save Money While Buying #10 Envelopes

Many places sell #10 envelopes, which means that there are plenty of chances to comparison shop for a good deal. Here are some of the places to check to see where you can get the best prices when you're buying business-sized envelopes:

  • Specialist online shops like Envelopes.com
  • Large online retailers like Amazon
  • Big box retailers like Walmart or KMart
  • Office supply stores like Staples or Office Depot
  • Grocery and drug stores
  • Warehouse stores like Sams Club or Costco

If you're lucky, you could also find #10s on sale at thrift stores, yard sales, and flea markets which usually offer deep discounts.

By shopping around these locations, you can save money buying #10s. Don't forget to use coupons and gift cards to reduce your envelope costs even more, when you have the opportunity.