Letter Envelopes

LUX 80lbs. 4 1/8" x 9 1/2" #10 Square Flap Envelopes, Gold Metallic, 500/BX~#|#~m004940416_sc7LUX 80lbs. 4 1/8" x 9 1/2" #10 Square Flap Envelopes, Gold Metallic, 500/BX~#|#~m005823910_sc7
Item: 384980
Model: 5360-07-500
No reviews yet
Price is $143.59
Unit of measure 500/Box
Free delivery by Thu, Jul 23
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LUX #10 Open End Envelopes (4 1/8 x 9 1/2) 50/Pack, Gold Metallic (7716-07-50)~#|#~57390F8F-815C-4112-B3745A57B0F0B132_sc7LUX #10 Open End Envelopes (4 1/8 x 9 1/2) 50/Pack, Gold Metallic (7716-07-50)~#|#~77409E69-4E56-4923-A99AD063E0721A49_sc7
Item: 24162006
Model: 7716-07-50
No reviews yet
Price is $31.19
Unit of measure 50/Pack
Delivery by Thu, Jul 23
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JAM Paper Strathmore Open End #10 Business Envelope, 4 1/8" x 9 1/2", Ivory Wove, 50/Pack (191165I)~#|#~sp132864373_sc7JAM Paper Strathmore Open End #10 Business Envelope, 4 1/8" x 9 1/2", Ivory Wove, 50/Pack (191165I)~#|#~sp132864372_sc7
Item: 1588692
Model: 191165I
Price is $28.29
Unit of measure 50/Pack
Delivery by Thu, Jul 23
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LUX 80lbs. 4 1/8" x 9 1/2" #10 Square Flap Envelopes, Flame Metallic Orange, 500/BX~#|#~m004940426_sc7LUX 80lbs. 4 1/8" x 9 1/2" #10 Square Flap Envelopes, Flame Metallic Orange, 500/BX~#|#~m005823908_sc7
Item: 385039
Model: 5360-26-500
No reviews yet
Price is $146.09
Unit of measure 500/Box
Free delivery by Thu, Jul 23
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LUX 80lb 4 1/8"x9 1/2" Open End #10 Envelopes W/Peel&Press, White, 500/BX~#|#~m000211244_sc7
Item: 515049
Model: 7716-WPC-500
No reviews yet
Price is $95.29
Free delivery by Thu, Jul 23
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JAM Paper #10 Business Foil Envelopes with Self-Adhesive Closure, 4.125 x 9.5, Gold, 25/Pack (1323305)~#|#~sp137086460_sc7JAM Paper #10 Business Foil Envelopes with Self-Adhesive Closure, 4.125 x 9.5, Gold, 25/Pack (1323305)~#|#~sp137086019_sc7
Item: 260895
Model: 1323305
No reviews yet
Price is $42.89
Unit of measure 25/Pack
Free delivery by Thu, Jul 23
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JAM Paper #10 Metallic Business Envelopes, 4.125 x 9.5, Stardream Gold, 25/Pack (SD5360 07)~#|#~m003905201_sc7JAM Paper #10 Metallic Business Envelopes, 4.125 x 9.5, Stardream Gold, 25/Pack (SD5360 07)~#|#~m003905200_sc7
Item: 261972
Model: SD5360 07
No reviews yet
Price is $25.49
Unit of measure 25/Pack
Delivery by Thu, Jul 23
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JAM Paper #10 Policy Business Colored Envelopes, 4.125 x 9.5, Blue Recycled, Bulk 500/Box (15880H)~#|#~m003904550_sc7JAM Paper #10 Policy Business Colored Envelopes, 4.125 x 9.5, Blue Recycled, Bulk 500/Box (15880H)~#|#~m003904549_sc7
Item: 1589641
Model: 15880H
No reviews yet
Price is $202.99
Unit of measure 500/Box
Free delivery by Thu, Jul 23
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LUX 80lbs. 4 1/8" x 9 1/2" #10 Open End Envelopes, Wisteria Purple, 250/BX~#|#~m000081288_sc7
Item: 388708
Model: LUX-7716-106-25
No reviews yet
Price is $114.89
Unit of measure 250/Box
Free delivery by Thu, Jul 23
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LUX 80lbs. 4 1/8" x 9 1/2" Metallic Square Flap Envelopes, Anthracite Metallic Gray, 1000/BX~#|#~m004940420_sc7LUX 80lbs. 4 1/8" x 9 1/2" Metallic Square Flap Envelopes, Anthracite Metallic Gray, 1000/BX~#|#~m005823900_sc7
Item: 385004
Model: 5360-15-1000
No reviews yet
Price is $277.59
Unit of measure 1000/Box
Free delivery by Thu, Jul 23
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LUX 4 1/8" x 9 1/2" #10 70lbs. Open End Envelopes, Garnet Red, 50/Pack~#|#~m000081272_sc7
Item: 281883
Model: EX7716-26-50
No reviews yet
Price is $55.29
Unit of measure 50/Pack
Free delivery by Thu, Jul 23
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JAM Paper #10 Business Envelope, 4 1/8" x 9 1/2", Green, 1000/Carton (15862B)~#|#~sp111772450_sc7JAM Paper #10 Business Envelope, 4 1/8" x 9 1/2", Green, 1000/Carton (15862B)~#|#~sp111772449_sc7
Item: 261287
Model: 15862B
No reviews yet
Price is $249.29
Unit of measure 1000/Carton
Free delivery by Thu, Jul 23
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Quality Park Reveal-N-Seal Security Tinted #10 Business Envelopes, 4 1/8" x 9 1/2", White Wove, 500/Box (QUA67218)~#|#~sp40319157_sc7
Item: QUA67218
Model: QUA67218
Price is $135.09
Unit of measure 500/Box
Free delivery by Wed, Jul 22
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Quality Park Redi-Seal Security Tinted Business Envelopes, 4 1/8" x 9 1/2", White, 500/Box (QUA11218)~#|#~sp46777632_sc7Quality Park Redi-Seal Security Tinted Business Envelopes, 4 1/8" x 9 1/2", White, 500/Box (QUA11218)~#|#~sp46777631_sc7
Item: QUA11218
Model: QUA11218
Price is $86.21
Unit of measure Box
Free delivery by Wed, Jul 22
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JAM Paper #10 Business Translucent Vellum Envelopes, 4.125 x 9.5, Primary Blue, Bulk 500/Box (PACV357H)~#|#~m003905168_sc7JAM Paper #10 Business Translucent Vellum Envelopes, 4.125 x 9.5, Primary Blue, Bulk 500/Box (PACV357H)~#|#~m003905167_sc7
Item: 1589618
Model: PACV357H
No reviews yet
Price is $377.99
Unit of measure 500/Box
Free delivery by Thu, Jul 23
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LUX 70lbs. 4 1/8" x 9 1/2" #10 Open End Envelopes, Baby Blue, 500/BX~#|#~m000081266_sc7
Item: 386933
Model: EX7716-13-500
No reviews yet
Price is $204.69
Unit of measure 500/Box
Free delivery by Thu, Jul 23
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LUX 80lb 4 1/8"x9 1/2" Open End #10 Envelopes, Navy Blue, 500/BX~#|#~m000081279_sc7
Item: 517160
Model: LUX-7716-103500
No reviews yet
Price is $211.89
Free delivery by Thu, Jul 23
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JAM Paper #10 Business Translucent Vellum Envelopes, 4.125 x 9.5, Primary Blue, 50/Pack (PACV357I)~#|#~m003905168_sc7JAM Paper #10 Business Translucent Vellum Envelopes, 4.125 x 9.5, Primary Blue, 50/Pack (PACV357I)~#|#~m003905167_sc7
Item: 1588572
Model: PACV357I
No reviews yet
Price is $39.99
Unit of measure 50/Pack
Free delivery by Thu, Jul 23
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JAM Paper #10 Policy Metallic Envelopes, 4.125 x 9.5, Stardream Silver, Bulk 500/Box (900905922H)~#|#~m004672038_sc7JAM Paper #10 Policy Metallic Envelopes, 4.125 x 9.5, Stardream Silver, Bulk 500/Box (900905922H)~#|#~m004672037_sc7
Item: 1589766
Model: 900905922H
No reviews yet
Price is $377.99
Unit of measure 500/Box
Free delivery by Thu, Jul 23
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JAM Paper #10 Business Foil Envelopes with Self-Adhesive Closure, 4.125 x 9.5, Red, 100/Pack (01323307B)~#|#~m000067476_sc7
Item: 260948
Model: 01323307B
No reviews yet
Price is $127.99
Unit of measure 100/Box
Free delivery by Thu, Jul 23
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LUX 80lbs. 4 1/8" x 9 1/2" #10 Business Envelopes W/Peel & Press, Smoke Gray, 1000/BX~#|#~m004940462_sc7LUX 80lbs. 4 1/8" x 9 1/2" #10 Business Envelopes W/Peel & Press, Smoke Gray, 1000/BX~#|#~m005824005_sc7
Item: 386341
Model: EX4860-22-1000
No reviews yet
Price is $165.49
Unit of measure 1000/Box
Free delivery by Thu, Jul 23
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LUX #10 Square Flap Envelopes (4 1/8 x 9 1/2) 50/Pack, Smoke (EX4860-22-50)~#|#~sp14807360_sc7
Item: 24260421
Model: EX4860-22-50
No reviews yet
Price is $26.79
Unit of measure 50/Pack
Delivery by Thu, Jul 23
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LUX 80lb 4 1/8"x9 1/2" Square Flap #10 Envelopes, Smoke Gray, 500/BX~#|#~m000161299_sc7
Item: 516408
Model: EX4860-22-500
Price is $139.29
Free delivery by Thu, Jul 23
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JAM Paper Strathmore Open End #10 Business Envelope, 4 1/8" x 9 1/2", Natural White Wove, 50/Pack (34992I)~#|#~m007159127_sc7JAM Paper Strathmore Open End #10 Business Envelope, 4 1/8" x 9 1/2", Natural White Wove, 50/Pack (34992I)~#|#~m007159126_sc7
Item: 1588542
Model: 34992I
No reviews yet
Price is $20.49
Unit of measure 50/Pack
Delivery by Thu, Jul 23
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JAM Paper #10 Policy Business Colored Envelopes, 4.125 x 9.5, Orange Recycled, 50/Pack (15887I)~#|#~m003904556_sc7JAM Paper #10 Policy Business Colored Envelopes, 4.125 x 9.5, Orange Recycled, 50/Pack (15887I)~#|#~m003904555_sc7
Item: 1588703
Model: 15887I
No reviews yet
Price is $26.09
Unit of measure 50/Pack
Delivery by Thu, Jul 23
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JAM Paper #10 Business Envelopes, 4.125 x 9.5, Baby Blue, Bulk 500/Box (2155778H)~#|#~5919944E-7278-4F67-B9B9763E17C6E6FD_sc7JAM Paper #10 Business Envelopes, 4.125 x 9.5, Baby Blue, Bulk 500/Box (2155778H)~#|#~CFA949F6-6990-4C05-988C673881FE92FF_sc7
Item: 1589634
Model: 2155778H
No reviews yet
Price is $138.79
Unit of measure 500/Box
Free delivery by Thu, Jul 23
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JAM Paper #10 Booklet Envelopes, 4 1/8" x 9 1/2", Dark Green, 100/Pack (21514959d)~#|#~7137717F-3BC5-46E5-814018B67B2006BE_sc7JAM Paper #10 Booklet Envelopes, 4 1/8" x 9 1/2", Dark Green, 100/Pack (21514959d)~#|#~3512B76B-324A-4D15-9DA55BE0B4169266_sc7
Item: 24604649
Model: 21514959d
No reviews yet
Price is $32.99
Unit of measure 100/Pack
Delivery by Thu, Jul 23
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JAM Paper Open End #10 Business Envelope, 4 1/8" x 9 1/2", Dark Red, 500/Pack (31511298H)~#|#~m002168474_sc7
Item: 1589630
Model: 31511298H
No reviews yet
Price is $152.99
Unit of measure 500/Box
Free delivery by Thu, Jul 23
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JAM Paper #10 Business Envelope, 4 1/8" x 9 1/2", Teal Blue, 50/Pack (63924024I)~#|#~sp134498426_sc7JAM Paper #10 Business Envelope, 4 1/8" x 9 1/2", Teal Blue, 50/Pack (63924024I)~#|#~sp134498425_sc7
Item: 2633057
Model: 63924024I
No reviews yet
Price is $34.09
Unit of measure 50/Pack
Delivery by Thu, Jul 23
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LUX 80lbs. 4 1/8" x 9 1/2" #10 Square Flap Envelopes W/Glue, Amethyst Metallic Purple, 250/BX~#|#~m004940421_sc7LUX 80lbs. 4 1/8" x 9 1/2" #10 Square Flap Envelopes W/Glue, Amethyst Metallic Purple, 250/BX~#|#~m005823899_sc7
Item: 385007
Model: 5360-17-250
No reviews yet
Price is $109.99
Unit of measure 250/Box
Free delivery by Thu, Jul 23
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JAM Paper #10 Metallic Business Envelopes, 4.125 x 9.5, Stardream Silver, 25/Pack (SD5360 06)~#|#~m004672467_sc7JAM Paper #10 Metallic Business Envelopes, 4.125 x 9.5, Stardream Silver, 25/Pack (SD5360 06)~#|#~m004672466_sc7
Item: 261992
Model: SD5360 06
No reviews yet
Price is $33.99
Unit of measure 25/Pack
Delivery by Thu, Jul 23
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JAM Paper Open End #10 Business Envelope, 4 1/8" x 9 1/2", Black, 50/Pack (900921796I)~#|#~sp121511957_sc7JAM Paper Open End #10 Business Envelope, 4 1/8" x 9 1/2", Black, 50/Pack (900921796I)~#|#~sp121511956_sc7
Item: 1588605
Model: 900921796I
No reviews yet
Price is $23.99
Unit of measure 50/Pack
Delivery by Thu, Jul 23
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JAM Paper #10 Policy Business Colored Envelopes, 4.125 x 9.5, Blue Recycled, 50/Pack (15880I)~#|#~m003904550_sc7JAM Paper #10 Policy Business Colored Envelopes, 4.125 x 9.5, Blue Recycled, 50/Pack (15880I)~#|#~m003904549_sc7
Item: 1588700
Model: 15880I
No reviews yet
Price is $26.09
Unit of measure 50/Pack
Delivery by Thu, Jul 23
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LUX Moistenable Glue #10 Window Envelope, 4 1/2" x 9 1/2", Electric Yellow, 50/Pack (4261-20-50)~#|#~m000081284_sc7
Item: 281895
Model: EX7716-12-50
Price is $74.89
Unit of measure 50/Pack
Free delivery by Thu, Jul 23
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LUX 70lbs. 4 1/8" x 9 1/2" #10 Square Flap Envelopes, Candy Pink, 1000/BX~#|#~m004940458_sc7LUX 70lbs. 4 1/8" x 9 1/2" #10 Square Flap Envelopes, Candy Pink, 1000/BX~#|#~m005824001_sc7
LUX 70lbs. 4 1/8" x 9 1/2" #10 Square Flap Envelopes, Candy Pink, 1000/BX is Out of stock
Item: 386322
Model: EX4860-14-1000
No reviews yet
Price is $169.69
Unit of measure 1000/Box
JAM Paper #10 Policy Business Envelopes, 4.125 x 9.5, Black Linen, 50/Pack (V01218I)~#|#~m003905223_sc7JAM Paper #10 Policy Business Envelopes, 4.125 x 9.5, Black Linen, 50/Pack (V01218I)~#|#~m003905222_sc7
JAM Paper #10 Policy Business Envelopes, 4.125 x 9.5, Black Linen, 50/Pack (V01218I) is Out of stock
Item: 1588604
Model: V01218I
No reviews yet
Price is $26.09
Unit of measure 50/Pack
LUX 60lbs. 4 1/8" x 9 1/2" #10 Regular Envelopes, Blue Parchment, 500/BX~#|#~m000081289_sc7
LUX 60lbs. 4 1/8" x 9 1/2" #10 Regular Envelopes, Blue Parchment, 500/BX is Out of stock
Item: 385531
Model: 6660-12-500
No reviews yet
Price is $95.49
Unit of measure 500/Box
JAM Paper Strathmore Open End #10 Business Envelope, 4 1/8" x 9 1/2", Ivory Wove, 500/Pack (191165H)~#|#~sp132864530_sc7JAM Paper Strathmore Open End #10 Business Envelope, 4 1/8" x 9 1/2", Ivory Wove, 500/Pack (191165H)~#|#~sp132864529_sc7
JAM Paper Strathmore Open End #10 Business Envelope, 4 1/8" x 9 1/2", Ivory Wove, 500/Pack (191165H) is Out of stock
Item: 1589693
Model: 191165H
No reviews yet
Price is $169.19
Unit of measure 500/Box
LUX #10 Regular Envelopes (4 1/8 x 9 1/2) 250/Box, 24lb. White Linen (WS-2960-250)~#|#~m004063955_sc7
LUX #10 Regular Envelopes (4 1/8 x 9 1/2) 250/Box, 24lb. White Linen (WS-2960-250) is Out of stock
Item: 2146397
Model: WS-2960-250
Price is $88.39
Unit of measure 250/Pack
LUX 70lbs. 4 1/8" x 9 1/2" #10 Square Flap Envelopes, Candy Pink, 500/BX~#|#~m004940458_sc7LUX 70lbs. 4 1/8" x 9 1/2" #10 Square Flap Envelopes, Candy Pink, 500/BX~#|#~m005824001_sc7
LUX 70lbs. 4 1/8" x 9 1/2" #10 Square Flap Envelopes, Candy Pink, 500/BX is Out of stock
Item: 386325
Model: EX4860-14-500
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Price is $142.49
Unit of measure 500/Box

Letter envelopes are an essential office supply for any home or office. These standard, versatile envelopes can be used to mail letters, checks, documents and more. At Staples, you can buy letter size envelopes in bulk in packs of anywhere from 25 to 2,500. Learn about the different types of letter envelopes below.

What Are Letter Envelopes?

A letter envelope is a sealable paper envelope typically measuring 4 ⅛ inches by 9 ½ inches, also known as a #10 envelope. Letter envelopes are not meant to contain thick or heavy objects. Rather, they’re meant to hold paper and other thin, light and flat materials. A letter-size envelope is also often compatible with a printer for those who want to print addresses rather than write them by hand. These #10 envelopes are the perfect size for mailing letters or documents because they are not too small to be accepted by postal services and not too big to require extra postage.

Types of Letter Envelopes

Letter envelopes also come in several different styles, the most common of which are described below.

  • Environmentally Friendly Envelopes - These are made from recycled paper and are great for households or businesses that do a lot of mailing to reduce environmental impact.
  • Business Envelopes - These envelopes include a clear plastic window for parts of the documents inside to be made visible. These windows have securely gummed closures to ensure that the contents of the envelope stay protected.
  • Multi-Colored Envelopes - Letter envelopes come in a variety of color options, including beige, pink, yellow, green, purple and more.
  • V-Flap Envelopes - The standard letter envelope is designed with a rectangular adhesive flap, but triangular, or “v-flap,” adhesive flaps are also available and are commonly used with greeting cards and invitations.
  • Linen Envelopes - Some letter envelopes come with a linen finish to set your letter apart and add an elegant touch.

How Do I Mail a Letter Envelope?

Here are the steps needed to mail a classic #10 letter envelope:

  1. On the side without the seal, write or print the recipient's address in the middle with a legible pen (pencil marks can dull or rub off in transit). Write the sender’s address in the envelope’s top left corner.
  2. In the top right corner, you will need to place adequate postage for the envelope to reach its destination.
  3. With the material you want to send inside the envelope, seal it by adding a light amount of moisture to the adhesive flap. If you don’t prefer to use your tongue, you can use a moist sponge or cotton swab to do this. Alternatively, you can even use tape or glue sticks to seal envelopes. Some letter envelope varieties are self-seal or peel-and-seal and are able to seal on their own without needing added moisture.
  4. Place the envelope in a USPS mailbox or bring it to a post office.