Colored Envelopes for Business: Sizes, Styles, and When to Use Them

Last updated: November 5, 2026

A colored envelope does one thing a white envelope cannot: it gets noticed before it is opened. For direct mail, reply envelopes, seasonal campaigns, and any mailing where response rate matters, the envelope color is the first signal the recipient sees. This guide covers the colored envelope formats available for business use, the two surface styles, and how to match the right format to each type of mailing.

Quick Summary

Colored envelopes for business come in two surface styles: wove (solid color, smooth finish) and starburst (bold printed pattern on the face). Both styles are available in multiple sizes from the compact #6 3/4 reply format up to the 9 x 12 flat mailer. Wove envelopes use a gum flap closure and are best for color-coded office mailings and reply envelopes. Starburst envelopes use a peel-and-seal closure and are designed for direct mail and promotional pieces where visual impact drives open rates.

• Two styles: wove (solid color, gum flap) and starburst (bold pattern, peel-and-seal)
• Sizes available: #6 3/4, #9, #10, 6 x 9, and 9 x 12
• #10 colored wove (4-1/8 x 9-1/2 in) is the standard format for business letters and billing in color
• #9 colored envelope (3-7/8 x 8-7/8 in) fits inside a #10 for reply and return use
• Color coding speeds mailing sorting when different departments or campaigns use different envelope colors
• Custom printing of logos and return addresses is available on all colored envelope formats

Two Colored Envelope Styles: Wove and Starburst

Colored business envelopes come in two surface styles. Each has a different purpose and closure type.

A wove colored envelope has a smooth surface finished in a solid color. The wove finish matches standard white business envelopes: clean texture and compatible with most laser and inkjet printers for return addresses or logos. The wove style uses a gum flap closure. This is the right format for professional colored envelopes in office correspondence, reply pieces, or color-coded billing runs.

A starburst colored envelope has a bold multi-color pattern across the face. The pattern stands out in a stack of mail before the envelope is opened. The starburst style uses a peel-and-seal closure with a pressure-sensitive strip, so no moisture is needed. This format suits promotional mailings, direct mail campaigns, seasonal promotions, and any piece where visual impact drives opens.

Browse the complete selection of colored envelopes by size and style.

Number 10 Colored Envelopes

The #10 is the standard business letter envelope. It measures 4-1/8 x 9-1/2 inches with an interior enclosure space of 4 x 9-1/4 inches. It holds a standard 8.5 x 11 sheet folded in thirds and qualifies for First-Class letter postage on contents under 3.5 ounces. Both wove and starburst styles are available in this size.

The #10 colored wove envelope has a solid-color surface and a gum flap closure. Colors include red, beige, and assorted shades for business use. The surface accepts laser and inkjet printing for return addresses and logos. This format suits billing statements, collection notices, gift certificates, and correspondence where color signals a different mail type than standard white envelopes.

The #10 starburst envelope uses the same outer dimensions but has a bold pattern across the face. The peel-and-seal closure needs no moisture, which speeds sealing in small promotional runs. Colors include red, blue, pink, and more. This format suits direct mail, seasonal promotions, and campaigns where the goal is to stand out in a pile of incoming mail.

See the #10 colored wove envelopes and the #10 starburst envelopes for specifications and color options.

Number 9 Colored Envelopes

The #9 envelope measures 3-7/8 x 8-7/8 inches. Its main role is as a reply envelope: a #9 fits inside a standard #10. It can be inserted as a pre-addressed return piece with invoices, statements, donation appeals, or promotional letters.

Color on a reply envelope serves a practical purpose that a white reply envelope does not. When the reply envelope stands out visually from the rest of the letter contents, it is easier for the recipient to notice and act on it. For fundraising and nonprofit development, colored reply envelopes track with higher return rates. They are easier to find when the reader comes back to the piece after setting it aside.

Both wove and starburst styles are available in the #9 format. The wove #9 comes in assorted colors including blue and red. The starburst #9 is available in a range of bright colors including orange, pink, green, blue, lemon, tangerine, cherry, lime, fuchsia, and red. Both use their respective closure types: gum flap for wove and peel-and-seal for starburst.

See the #9 colored wove envelopes and the #9 starburst envelopes for color options and details.

Number 6 3/4 Colored Envelopes

The #6 3/4 envelope measures 3-5/8 x 6-1/2 inches. It is a smaller format than the #9 and is used for short notes, small reply pieces, invoice enclosures, and promotional cards. It also fits inside most #10 envelopes, making it a second reply-envelope option for mailings where a smaller enclosure is preferred.

The wove #6 3/4 is available in vibrant light blue and uses a gum flap closure. The smooth finish works with standard printers for return address and logo printing. Reviewers note using this format in charity campaigns where different envelope colors are assigned to different mailing segments for easy sorting and tracking.

The starburst #6 3/4 comes in pink, green, yellow, red, and blue with a bold pattern on the face and a peel-and-seal closure. This format works well for promotional inserts, holiday cards, and small direct mail pieces where a compact but visually distinctive envelope fits the campaign.

See the #6 3/4 colored wove envelopes and the #6 3/4 starburst envelopes.

6 x 9 Colored Envelopes

The 6 x 9 booklet envelope opens on the long 9-inch edge and holds a standard 8.5 x 11 sheet folded in half, a 5 x 7 card flat, a brochure, or a small catalog. At 6 inches tall, it falls just below the USPS letter-rate height limit of 6-1/8 inches, so it can qualify for First-Class letter postage on light contents under 3.5 ounces.

The 6 x 9 colored envelope is available in the starburst style with a peel-and-seal closure. Colors include yellow, green, and other vibrant options. The starburst pattern on the face makes the 6 x 9 format suited for promotional mailings, event invitations, and campaign pieces that benefit from a larger envelope format and a high-visibility exterior.

For a larger catalog or flat document that cannot be folded, the 9 x 12 format is the alternative (see the next section). For a smaller format that still qualifies for letter rate, the starburst #10 covers that use case.

See the 6 x 9 starburst booklet envelopes for color options and specifications.

9 x 12 Colored Envelopes

The 9 x 12 is a flat-mail format. It holds a standard 8.5 x 11 sheet with about 1/4 inch of clearance on each side and 1/2 inch at the top, so documents arrive without folding. The interior enclosure space is 8.75 x 11.5 inches. USPS classifies the 9 x 12 as a flat rather than a letter, so postage is higher than the letter rate.

The 9 x 12 starburst envelope uses a gummed seal closure rather than peel-and-seal, making it a lower-cost option for this large format. Colors include yellow, pink, lime, blue, and additional options. The starburst pattern makes the piece visible in mail bins before it is opened. This matters for catalog mailings, presentation packets, and flat-mail campaigns where standing out in a stack of standard white flats is the goal.

See the 9 x 12 starburst booklet envelopes for specifications and color options.

How to Use Color Coding in Your Mailings

Color coding assigns different envelope colors to different mailing types, departments, or recipient groups. It is most useful in organizations that process large mailing volumes across multiple purposes and need a quick visual way to sort, track, or prioritize incoming and outgoing pieces.

Common color coding applications in business include:

• Department sorting: Each department uses a different colored envelope for outgoing correspondence, so incoming replies are easy to route without reading the contents
• Campaign tracking: A fundraising or direct mail campaign assigns one color per mailing segment, making it easy to track which segment is generating replies as they come in
• Priority signaling: A colored envelope signals to the recipient that the piece is not routine correspondence and should be opened before standard white mail
• Seasonal campaigns: Using color to match the season or event (holiday, spring campaign, year-end appeal) creates a visual link between the mailing and the occasion
• Reply envelope matching: Matching the reply envelope color to the outer mailing color makes the response piece easier to find and improves return rates

The wove colored envelopes are the practical choice for departmental color coding because the solid color is consistent across the batch, the gum flap is straightforward to seal in volume, and the smooth surface can carry a printed return address or department identifier. The starburst style is better suited when visual distinctiveness is the primary goal rather than systematic color assignment.

Direct Mail and Promotional Uses

In a direct mail context, envelope design affects whether the piece gets opened. Most business mail arrives in a standard white #10 envelope. A piece that arrives in a colored envelope with a bold pattern stands out from that baseline before the recipient makes any decision about its contents.

The starburst envelope series is designed for this role. The pattern is intentionally eye-catching rather than conservative, which makes it appropriate for promotions, limited-time offers, seasonal sales, event announcements, and campaigns where urgency or excitement is part of the message. Because the starburst peel-and-seal closure does not require moisture, it is practical for small-batch runs where sealing by hand is faster than setting up a mailing machine.

For promotional use, the size selection matters as much as the color. A #10 starburst keeps postage at letter rate and holds a standard letter or one-page offer. A 6 x 9 starburst holds a half-fold brochure and may qualify for letter-rate postage.

A 9 x 12 starburst holds a full catalog or product sheet flat, but requires flat-mail postage. Match the size to what you are mailing and your postage budget.

When to Use Colored Reply Envelopes

A reply envelope is most effective when it is easy to find after the recipient has reviewed the mailing. A colored reply envelope is easier to locate in a stack of papers than a white one, which can blend into the letter contents or get set aside with other documents.

Situations where a colored reply envelope improves response rates include:

• Fundraising and nonprofit development appeals: The colored reply piece stands out from the appeal letter and accompanying materials, making it easier for the donor to find and use after deciding to give
• Invoice and billing reply envelopes: A colored #9 or #6 3/4 inside a billing statement envelope makes the payment return piece immediately visible
• Event RSVPs: Colored reply envelopes signal urgency and make the response mechanism stand out from the rest of the invitation package
• Political and advocacy mail: Colored reply pieces are standard in advocacy mail where the goal is a fast, high-volume response from the recipient list

The #9 colored envelope is the most commonly used reply format because it fits inside a standard #10 outer envelope. The #6 3/4 is a smaller alternative for compact mailings. Both are available in wove and starburst styles, though the wove format is typically more appropriate for professional correspondence and billing, while the starburst format fits better in promotional and campaign contexts.

Custom Printing on Colored Envelopes

All colored envelope formats on this site support custom printing. The standard option is a logo and return address printed on the face of the envelope in one or two colors. Custom printing is available on blank stock across the #6 3/4, #9, and #10 wove formats, and on the starburst formats in all sizes.

Custom printing on a colored envelope requires a proof before production. The printing goes on top of the envelope's surface color or pattern, so logo placement and color contrast matter more on a colored envelope than on a standard white envelope. A logo in a dark color stands out on a light wove background. On a starburst pattern, a logo typically works best placed in a solid-color area of the face rather than over the pattern.

Blank stock ships same or next business day. Custom printed orders ship 7 to 10 business days after proof approval. For seasonal campaigns, this lead time should be factored into your mailing schedule.

How to Choose the Right Colored Envelope

The right colored envelope depends on the type of mailing, the size of the document you are sending, and the goal of the piece.

For color selection on wove envelopes, match the color to your brand palette or to the purpose of the mailing. A bold red signals urgency, blue reads as professional, and lighter shades work well for reply envelopes that should be distinctive but not dominate the mailing package.

For size selection, start with what you are mailing. A standard folded letter fits in a #10 format. A flat document needs the 9 x 12. A small enclosure or reply piece uses the #9 or #6 3/4.

Choose the style (wove or starburst) based on whether the goal is professional correspondence or promotional visibility.

Browse the full range of colored envelopes by size and style to find the right format for your next order.