The Guide to Finding the Right Envelope!

Choosing the right envelope sizes for each business application can be hard. There are many different sizes that are best used for specific mailings, and you might want to have different types of envelopes on hand for interoffice mail as well. Since many envelope sizes are labeled by a single number, like #7 or #10, it can be tough to figure out which ones you need. At The Supplies Shops, we’ve put together this handy envelope size guide to help you compare envelopes with various sizes, materials, and closure designs. Check out the graphics above for an overview, then see below for more information about each type of business envelope and to view helpful envelope size charts!

Regular Envelopes

Regular envelopes feature the standard envelope sizes you see used most frequently for mailings. However, there isn’t just one type of business envelope for this category. This product range includes the popular #10 envelope, which measures 4 1/8″ x 9 1/2″ and is often considered to be the “classic” U.S. envelope size for business purposes. In addition, #9 regular envelopes (3-7/8″ x 8-7/8″) are another one of the most popular commercial-sized envelopes available. The #9 envelope style is commonly used as a reply envelope for invoices and business mailings, sent to recipients inside #10 envelopes in order to mail something back to the sender.

Other popular regular envelopes include:

• #5 Regular Envelopes (3-1/8″ x 5-1/2″) – Same size as a coin envelope, but side opening. It can be mailed inside of other envelopes or used to store smaller items. This envelope cannot be mailed by itself.
• #6-1/4 Regular Envelopes (3-1/2″ x 6″) – The smallest commercial envelope size available, it’s just the right size for everyday usage; perfect for mailing small items such as a folded personal check. Use to store tickets for an upcoming event or store reminders, coupons, recipes, social security cards, or other items that require organization in your personal records.
• #6-3/4 Regular Envelopes (3-5/8″ x 6-1/2″) – Great for personal or corporate business. This size could be used for invoices, sales pieces, checks, or correspondence.
• #7 Regular Envelopes (3-3/4″ x 6-3/4″) – The ideal model that is suitable for short business correspondence or home office needs.
• #7-1/2 Regular Envelopes (3-15/16″ x 7-1/2″) – It can be mailed inside of other envelopes and used as a return envelope or be used as a mailer for smaller envelopes.
• #8-5/8 Regular Envelopes (3-5/8″ x 8-5/8″) – Popular as business payment envelopes, it is also ideal for checks (no need to fold business-sized checks).
• #9-5/8 Regular Envelopes (4-1/2″ x 9-5/8″) – These are slightly larger than the #9 envelope so it can fit more folded pages.
• #11 Regular Envelopes (4-1/2″ x 10-3/8″) – The larger size allows for more folded pages, storage, and can act as an outer envelope to the #10 envelope being used as a return envelope.

All regular envelopes feature a solid front with no window, and a basic flap on the back. Some regular envelopes have special features, including security tint to conceal the contents, and pre-moistened adhesive flaps for easy closure. Therefore, businesses use these envelopes to send invoices, checks, letters, and other types of mailings. If you need regular business envelopes, you’ll be able to choose from a wide range of colors, including pastels and bright colors.

Window Envelopes

Window envelopes feature one or more openings on the front of the envelope that allows the contents inside the envelope to show through. Single window envelopes have just one opening for the mailing address, whereas double window envelopes have an opening for the return address as well. Full face envelopes have an opening on the entire front of the envelope, giving a view of the contents inside. Choose from a wide array of colors and sizes of envelopes to coordinate with your mailing needs, including window envelopes designed for standard business checks.

Common window envelope sizes:

• #6-3/4 Window Envelopes (3-5/8″ x 6-1/2″) – Fits a personal check.
• #8-5/8 Window Envelopes (3-5/8″ x 8-5/8″) – Great for sending check payments from accounting software like Quickbooks.
• #9 Window Envelopes (3-7/8″ x 8-7/8″)– This size fits comfortably inside a standard #10 envelope, so is often used as a return envelope.
• #10 Window Envelopes (4-1/8″ 9-1/2″)– Standard business envelope. Fits an 8 1/2″ x 11″ piece of paper folded in thirds.

One thing to keep in mind when ordering window envelopes is whether you need them to go through your printer. If that’s the case, you’ll need envelopes with a thermal window like our digi-clear laser compatible window envelopes that can withstand the high temperatures inside the printer without being warped or melted.

Square Envelopes

Square envelopes are square and symmetrical, appealing to the eye and very stylish. Most square styles have square flaps on the back, but a few have deep triangular contour flaps that nicely offset the square envelope. Sizes range from miniature 5″ x 5″ square envelopes to 13″ x 13″ square envelopes. They are most commonly used with baronial cards for informal mailings, social invitations, and commercial announcements. This type of envelope comes in a wide range of colors, which is great for branding and for invitations to seasonal events or festive occasions. Keep in mind that when mailing square envelopes through the USPS, you will need additional postage because of the shape.

Learn more about the variety of announcement and invitation envelopes we have and their uses on our site >>>

Catalog Envelopes

The main feature of open end envelopes, also known as catalog envelopes, is the placement of the envelope flap on the short end of the envelope. With or without windows, these durable, high-quality envelopes come in brown kraft, white, and bright or pastel colors. With so many options, first select your size and material (paper or Tyvek). Then, select the appropriate closure mechanism: metal clasp, ungummed, remoistening seal, or pressure sensitive seal. There are also clasp envelopes that provide are an alternative to the gum closure. Also, filters in the left column will help you sort for specific needs.

You can choose windowless catalog envelopes or window catalog envelopes. Windowless catalog envelopes ensure that the contents of your package are kept hidden. On the other hand, window catalogs are produced with 28# white sulphite material and have multiple window options so the necessary information on your mail piece can be seen. Catalog envelopes are used for heavy mailing and shipping requirement such as: booklets, bulky documents, catalogs, magazines, sales literature, and more! These envelopes range from 2-1/2″ x 4-1/4″ to 22″ x 27″ to fit any size document.

Booklet Envelopes

Booklet envelopes are designed to accommodate larger and thicker mailings, including annual reports, brochures, catalogs, and sales literature. These envelopes are also ideal for important documents that should not be folded to fit into a standard envelope. They look professional and help to create branding opportunities for your business. These envelopes range from 4-3/16″ x 9-1/2″ to 12″ x 16″ to fit any size document. The 9″ x 12″ booklet envelope is perfect for mailing unfolded sheets of paper. The 5-3/8″ x 8-7/8″ envelope is ideal for mailing a sheet of paper that is folded in half.

One of the biggest decisions you’ll need to make when choosing your booklet envelopes is whether or not to include a window on the front. Some businesses prefer a flat, windowless appearance for these envelopes in order to allow for including a variety of items to be sent and addresses to be printed individually on the envelope itself. However, if you’re planning a big mailing, you can streamline the process by having addresses printed on the document so that it shows through the clear window. Since our booklet envelopes come with such a wide range of envelope window options, including everything from large showcase windows to small corner windows, you can make sure you get a format that’s optimized for your mailing needs.

Remittance Envelopes

Order your remittance envelopes from the Supplies Shops and save big on bulk orders. Remittance and collection envelopes are used by churches, charities, and schools for donations. We carry a wide variety of remittance envelopes in different colors, sizes, and styles. Choose from #6-1/4 envelopes, #6-3/4 envelopes, or #9 envelopes for your convenience.

#6-1/4 envelopes have a large printing surface making them suitable to be used as a return envelope. #6-1/4 remittance envelopes measure 3-1/2″ x 6-1/4″ and offer a choice of nine colors or standard white 24# stock. This size is ideal for mail order, subscriptions, donations, coupons, and other general remittance needs. Also, #6-3/4 envelopes can be used as a return envelope. #6-3/4 remittance envelopes measure 3-5/8″ x 6-1/2″ and offer a choice of nine colors or standard white 24# stock. #9 envelopes have a large printing surface and can be used as return envelopes. #9 remittance envelopes measure 3-7/8″ x 8-7/8″ and are commonly put inside of #10 envelopes.

Coin Envelopes

Despite the increasing use of digital payment methods, currency in the form of coins and paper money is still very much in use in our society. This style is still made of heavy-duty paper to ensure envelopes can hold numerous coins without buckling under the weight. What has improved over the years is the number of money envelope sizes available. Our money envelope measurements range from #00 to #7H, and we leave it up to you to determine what size works best for collecting monies or other uses.

Despite the name, people find them useful for storing all sorts of little items that would normally get lost or create messy clutter. Consider using these envelopes for storing and organizing items such as nails, bolts and screws, thumbtacks, jewelry beads, stones and metal backing or wires, paper fasteners, small machine parts, seeds, stamps, and numerous other small items.

Specialty Envelopes

Specialty envelopes help you achieve specific communication, marketing, and sales goals that cannot be met by common standard envelopes. There are also times when the standard envelope size is fine, but you prefer to use an alternative envelope design, which suits your purposes much better. Specialty envelopes are different in material or design from standard envelopes, and are designed to make business operations go more smoothly.

Many of our specialty envelope categories are designed for specific uses to make your shopping experience a breeze. Included in popular designs are specialty envelopes designed to hold currency. Churches enjoy distributing our offering envelopes to their congregations to encourage regular tithing. These envelopes come in a range of attractive colors and they’re a cinch to seal. Money gift envelopes are popular for birthdays, graduations, and holidays, and you can order your desired quantities of our attractive blank style or choose the cheerful holiday style. Keep monetary deposits protected at all times with our bank deposit envelopes.

Some popular specialty envelopes are:

If you are still unsure about the envelope you need or have any additional questions email us at [email protected] or call us at 855-632-8520. If our standard envelopes do not fit your needs, we can customize envelopes to your specifications. Click the link below to fill out a quote form.

Click Here to Complete the Custom Envelope Quote Form