Letter Envelopes

JAM Paper #10 Self Seal Policy Envelopes, 4 1/8" x 9 1/2", Strathmore White, 50/Pack (7716-WLI-50)~#|#~6E821E8F-5177-4680-BAA135A9177556E2_sc7JAM Paper #10 Self Seal Policy Envelopes, 4 1/8" x 9 1/2", Strathmore White, 50/Pack (7716-WLI-50)~#|#~E455C262-24B6-42A8-BC866CFE5F843B19_sc7
Item: 24604525
Model: 7716-WLI-50
No reviews yet
Price is $13.95
Unit of measure 50/Pack
Delivery by Wed, Jul 22
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JAM Paper #10 Business Envelope, 4 1/8" x 9 1/2", Baby Pink, 25/Pack (2155777)~#|#~m002934212_sc7JAM Paper #10 Business Envelope, 4 1/8" x 9 1/2", Baby Pink, 25/Pack (2155777)~#|#~m002934211_sc7
Item: 261385
Model: 2155777
Price is $20.49
Unit of measure 25/Pack
Delivery by Wed, Jul 22
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JAM Paper #10 Business Envelope, 4 1/8" x 9 1/2", Violet Purple, 25/Pack (15864)~#|#~sp112110499_sc7JAM Paper #10 Business Envelope, 4 1/8" x 9 1/2", Violet Purple, 25/Pack (15864)~#|#~sp112110498_sc7
Item: 263887
Model: 15864
Price is $20.49
Unit of measure 25/Pack
Delivery by Wed, Jul 22
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JAM Paper Strathmore #10 Business Envelope, 4 1/8" x 9 1/2", Bright White, 25/Pack (18506)~#|#~m007063336_sc7JAM Paper Strathmore #10 Business Envelope, 4 1/8" x 9 1/2", Bright White, 25/Pack (18506)~#|#~m007063335_sc7
Item: 263980
Model: 18506
Price is $20.49
Unit of measure 25/Pack
Delivery by Wed, Jul 22
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JAM Paper Peel & Seal #10 Business Envelope, 4 1/8" x 9 1/2", Christmas Green, 25/Pack (86555)~#|#~6D72CF40-FFBC-49D2-943889305B5B19A6_sc7
Item: 261275
Model: 86555
Price is $10.29
Unit of measure 25/Pack
Delivery by Wed, Jul 22
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JAM Paper #10 Policy Business Envelopes, 4 1/8" x 9 1/2", Aqua Blue, 25/Pack (21520986)~#|#~m002934469_sc7JAM Paper #10 Policy Business Envelopes, 4 1/8" x 9 1/2", Aqua Blue, 25/Pack (21520986)~#|#~m003904907_sc7
Item: 363434
Model: 21520986
No reviews yet
Price is $14.89
Unit of measure 25/Pack
Delivery by Wed, Jul 22
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JAM Paper Self Seal #10 Business Envelopes, 4 1/8" x 9 1/2", White, 250/Pack (75746-250)~#|#~sp228873484_sc7JAM Paper Self Seal #10 Business Envelopes, 4 1/8" x 9 1/2", White, 250/Pack (75746-250)~#|#~sp228873483_sc7
Item: 24578367
Model: 75746-250
No reviews yet
Price is $72.59
Unit of measure 250/Pack
Free delivery by Wed, Jul 22
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JAM Paper Strathmore Open End #10 Business Envelope, 4 1/8" x 9 1/2", Bright White Wove, 50/Pack (64933I)~#|#~sp112110502_sc7JAM Paper Strathmore Open End #10 Business Envelope, 4 1/8" x 9 1/2", Bright White Wove, 50/Pack (64933I)~#|#~sp112110501_sc7
Item: 1588544
Model: 64933I
No reviews yet
Price is $19.69
Unit of measure 50/Pack
Delivery by Wed, Jul 22
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JAM Paper Open End #10 Business Envelope, 4 1/8" x 9 1/2", Natural, 50/Pack (900926651I)~#|#~sp132864269_sc7JAM Paper Open End #10 Business Envelope, 4 1/8" x 9 1/2", Natural, 50/Pack (900926651I)~#|#~sp132864268_sc7
Item: 1588594
Model: 900926651I
Price is $20.49
Unit of measure 50/Pack
Delivery by Wed, Jul 22
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JAM Paper Peel & Seal #10 Business Envelope, 4 1/8" x 9 1/2", Christmas Red, 500/Pack (11789H)~#|#~sp36388124_sc7JAM Paper Peel & Seal #10 Business Envelope, 4 1/8" x 9 1/2", Christmas Red, 500/Pack (11789H)~#|#~sp36388044_sc7
Item: 1589659
Model: 11789H
No reviews yet
Price is $155.59
Unit of measure 500/Box
Free delivery by Wed, Jul 22
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JAM Paper Peel & Seal #10 Kraft Business Envelope, 4 1/8" x 9 1/2", Christmas Red, 1000/Carton (11789B)~#|#~sp36388124_sc7JAM Paper Peel & Seal #10 Kraft Business Envelope, 4 1/8" x 9 1/2", Christmas Red, 1000/Carton (11789B)~#|#~sp36388044_sc7
Item: 260851
Model: 11789B
Price is $261.29
Unit of measure 1000/Carton
Free delivery by Wed, Jul 22
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LUX 4 1/8" x 9 1/2" #10 80lbs. Square Flap Envelopes, Silver Metallic, 50/Pack~#|#~m004940415_sc7LUX 4 1/8" x 9 1/2" #10 80lbs. Square Flap Envelopes, Silver Metallic, 50/Pack~#|#~m005823916_sc7
Item: 281934
Model: 5360-06-50
No reviews yet
Price is $23.59
Unit of measure 50/Pack
Delivery by Wed, Jul 22
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LUX #10 Open End Envelopes (4 1/8 x 9 1/2) 50/Pack, Silver Metallic (7716-06-50)~#|#~sp12274947_sc7LUX #10 Open End Envelopes (4 1/8 x 9 1/2) 50/Pack, Silver Metallic (7716-06-50)~#|#~sp12275008_sc7
Item: 24162063
Model: 7716-06-50
Price is $31.19
Unit of measure 50/Pack
Delivery by Wed, Jul 22
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JAM Paper #10 Business Foil Envelopes with Peel & Seal Closure, 4 1/8" x 9 1/2", Silver, 25/Pack (1323306)~#|#~m004671920_sc7JAM Paper #10 Business Foil Envelopes with Peel & Seal Closure, 4 1/8" x 9 1/2", Silver, 25/Pack (1323306)~#|#~m004671919_sc7
Item: 260896
Model: 1323306
No reviews yet
Price is $41.89
Unit of measure 25/Pack
Free delivery by Wed, Jul 22
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LUX #10 Square Flap Envelopes (4 1/8 x 9 1/2) 50/Pack, Midnight Black (F-4560-B-50)~#|#~sp14807461_sc7
Item: 24260629
Model: F-4560-B-50
Price is $12.69
Unit of measure 50/Pack
Delivery by Wed, Jul 22
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LUX 80lbs. 4 1/8" x 9 1/2" #10 Square Flap Envelopes, Gold Metallic, 1000/BX~#|#~m004940416_sc7LUX 80lbs. 4 1/8" x 9 1/2" #10 Square Flap Envelopes, Gold Metallic, 1000/BX~#|#~m005823910_sc7
Item: 384975
Model: 5360-07-1000
No reviews yet
Price is $279.99
Unit of measure 1000/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, 25/Pack (PACV357)~#|#~m003905168_sc7JAM Paper #10 Business Translucent Vellum Envelopes, 4.125 x 9.5, Primary Blue, 25/Pack (PACV357)~#|#~m003905167_sc7
Item: 262213
Model: PACV357
No reviews yet
Price is $22.69
Unit of measure 25/Pack
Delivery by Wed, Jul 22
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JAM Paper #10 Business Strathmore Envelopes, 4.125 x 9.5, Bright White Wove, Bulk 500/Box (64933H)~#|#~sp112110502_sc7JAM Paper #10 Business Strathmore Envelopes, 4.125 x 9.5, Bright White Wove, Bulk 500/Box (64933H)~#|#~sp112110501_sc7
Item: 1589697
Model: 64933H
No reviews yet
Price is $170.39
Unit of measure 500/Box
Free delivery by Wed, Jul 22
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LUX 70lbs. 4 1/8" x 9 1/2" #10 Square Flap Envelopes, Grocery Bag Brown, 250/BX~#|#~m004940396_sc7LUX 70lbs. 4 1/8" x 9 1/2" #10 Square Flap Envelopes, Grocery Bag Brown, 250/BX~#|#~m005823987_sc7
Item: 384583
Model: 4860-GB-250
No reviews yet
Price is $75.09
Unit of measure 250/Box
Free delivery by Wed, Jul 22
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JAM Paper Open End #10 Business Envelope, 4 1/8" x 9 1/2", Fuchsia Pink, 50/Pack (15847I)~#|#~m003904529_sc7JAM Paper Open End #10 Business Envelope, 4 1/8" x 9 1/2", Fuchsia Pink, 50/Pack (15847I)~#|#~m003904528_sc7
Item: 1588564
Model: 15847I
Price is $20.49
Unit of measure 50/Pack
Delivery by Wed, Jul 22
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JAM Paper Open End #10 Business Envelope, 4 1/8" x 9 1/2", Dark Purple, 50/Pack (563912516I)~#|#~sp132864355_sc7JAM Paper Open End #10 Business Envelope, 4 1/8" x 9 1/2", Dark Purple, 50/Pack (563912516I)~#|#~sp132864354_sc7
Item: 1588603
Model: 563912516I
No reviews yet
Price is $20.49
Unit of measure 50/Pack
Delivery by Wed, Jul 22
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LUX #10 Regular Envelopes (4 1/8 x 9 1/2) 50/Box, White w/ Simple Seal~#|#~m004063975_sc7
Item: 2147426
Model: 28726-50
No reviews yet
Price is $31.19
Unit of measure 50/Pack
Delivery by Wed, Jul 22
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Quality Park Flap-Stik V-Flap Security Tinted #10 Business Envelope, 4 1/2" x 9 1/2", White, 500/Box (90030)~#|#~s0462616_sc7
Item: 831281
Model: QUA90030
No reviews yet
Price is $48.69
Unit of measure 500/Box
Free Next-Day eligible by Mon, Jul 20
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JAM Paper #10 Policy Business Strathmore Envelopes, 4.125 x 9.5, Natural White Wove, 25/Pack (191249)~#|#~m007063366_sc7JAM Paper #10 Policy Business Strathmore Envelopes, 4.125 x 9.5, Natural White Wove, 25/Pack (191249)~#|#~m007049471_sc7
Item: 262548
Model: 191249
Price is $14.89
Unit of measure 25/Pack
Delivery by Wed, Jul 22
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JAM Paper #10 Business Envelope, 4 1/8" x 9 1/2", Red, 25/Pack (67161)~#|#~sp112110506_sc7JAM Paper #10 Business Envelope, 4 1/8" x 9 1/2", Red, 25/Pack (67161)~#|#~sp112110505_sc7
Item: 260833
Model: 67161
Price is $20.49
Unit of measure 25/Pack
Delivery by Wed, Jul 22
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JAM Paper Strathmore #10 Business Envelope, 4 1/8" x 9 1/2", Bright White Wove, 25/Pack (64933)~#|#~sp112110502_sc7JAM Paper Strathmore #10 Business Envelope, 4 1/8" x 9 1/2", Bright White Wove, 25/Pack (64933)~#|#~sp112110501_sc7
Item: 262529
Model: 64933
Price is $19.69
Unit of measure 25/Pack
Delivery by Wed, Jul 22
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Over 30
LUX #10 Regular Envelopes (4 1/8 x 9 1/2) 500/Box, 24lb. White Linen (WS-2960-500)~#|#~m004063955_sc7
Item: 2146391
Model: WS-2960-500
No reviews yet
Price is $139.59
Unit of measure 500/Pack
Free delivery by Wed, Jul 22
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JAM Paper Self Seal #10 Business Envelopes, 4 1/8" x 9 1/2", Blue, 250/Pack (5360-13-250)~#|#~sp228873252_sc7
Item: 24578290
Model: 5360-13-250
No reviews yet
Price is $78.09
Unit of measure 250/Pack
Free delivery by Wed, Jul 22
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LUX 60lbs. 4 1/8" x 9 1/2" #10 Business Envelopes, White With Silver LUX Lining, 250/BX~#|#~m000081264_sc7
Item: 387906
Model: FLWH4260-03-250
No reviews yet
Price is $66.29
Unit of measure 250/Box
Free delivery by Wed, Jul 22
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LUX Moistenable Glue Security Tinted #10 Business Envelope, 4 1/8" x 9 1/2", White, 250/Pack (WS-2652-250)~#|#~m004064021_sc7
Item: 2147234
Model: WS-2652-250
No reviews yet
Price is $50.39
Unit of measure 250/Pack
Free delivery by Wed, Jul 22
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LUX #10 Window Envelopes, 4 1/8" x 9 1/2", 24 lb. White, Machine Insertable, 1000 Qty (28460-MI-1M)~#|#~m004064026_sc7
Item: 2146382
Model: 28460-MI-1M
No reviews yet
Price is $86.99
Unit of measure 1000/Pack
Free delivery by Wed, Jul 22
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LUX #10 Regular Envelopes (4 1/8 x 9 1/2) 50/Box, 24lb. Natural Linen (WS-2961-50)~#|#~m004063954_sc7
Item: 2146462
Model: WS-2961-50
No reviews yet
Price is $32.29
Unit of measure 50/Pack
Delivery by Wed, Jul 22
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LUX #10 Regular Envelopes (4 1/8 x 9 1/2) 50/Pack, Mandarin (LUX-4260-11-50)~#|#~sp12274947_sc7LUX #10 Regular Envelopes (4 1/8 x 9 1/2) 50/Pack, Mandarin (LUX-4260-11-50)~#|#~sp12275002_sc7
Item: 24162073
Model: LUX-4260-11-50
Price is $22.79
Unit of measure 50/Pack
Delivery by Wed, Jul 22
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LUX Moistenable Glue #10 Business Envelope, 4 1/8" x 9 1/2", Bright White, 500/Pack (43687-500)~#|#~sp14807479_sc7
Item: 24261001
Model: 43687-500
Price is $39.89
Unit of measure 500/Pack
Free delivery by Wed, Jul 22
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LUX 4 1/8" x 9 1/2" #10 70lbs. Open End Envelopes, Grocery Bag Brown, 50/Pack~#|#~m000081273_sc7
Item: 281884
Model: 7716-GB-50
No reviews yet
Price is $22.19
Unit of measure 50/Pack
Delivery by Wed, Jul 22
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LUX 80lb 4 1/8"x9 1/2" Open End #10 Envelopes W/Peel&Press, White, 250/BX~#|#~m000211244_sc7
Item: 515057
Model: 7716-WPC-250
No reviews yet
Price is $127.99
Free delivery by Wed, Jul 22
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JAM Paper #10 Business Envelope, 4 1/8" x 9 1/2", Blue, 25/Pack (15861)~#|#~sp111772444_sc7JAM Paper #10 Business Envelope, 4 1/8" x 9 1/2", Blue, 25/Pack (15861)~#|#~sp111772442_sc7
JAM Paper #10 Business Envelope, 4-1/8" x 9-1/2", Blue, 25/Pack (15861) is Out of stock
Item: 263914
Model: 15861
Price is $10.29
Unit of measure 25/Pack
LUX 70lb 4 1/8"x9 1/2" Square Flap #10 Envelopes, Baby Blue, 250/BX~#|#~m004940457_sc7LUX 70lb 4 1/8"x9 1/2" Square Flap #10 Envelopes, Baby Blue, 250/BX~#|#~m005824016_sc7
LUX 70lb 4 1/8"x9 1/2" Square Flap #10 Envelopes, Baby Blue, 250/BX is Out of stock
Item: 516411
Model: EX4860-13-250
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Price is $58.49
LUX Square Flap Self Seal #10 Invitation Envelope, 4 1/2" x 9 1/2", Candy Pink, 50/Pack (EX4860-14-50)~#|#~sp14807476_sc7
LUX Square Flap Self Seal #10 Invitation Envelope, 4 1/2" x 9 1/2", Candy Pink, 50/Pack (EX4860-14-50) is Out of stock
Item: 24261022
Model: EX4860-14-50
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Price is $25.89
Unit of measure 50/Pack
JAM Paper #10 Booklet Envelope, 4 1/8" x 9 1/2", Blue, 100/Pack (15861d)~#|#~05DEE4CF-C543-4869-8645BDAA8DAA7AAE_sc7JAM Paper #10 Booklet Envelope, 4 1/8" x 9 1/2", Blue, 100/Pack (15861d)~#|#~193F6945-35C5-4CB0-AB9DDE35D5470183_sc7
JAM Paper #10 Booklet Envelope, 4 1/8" x 9 1/2", Blue, 100/Pack (15861d) is Out of stock
Item: 24604579
Model: 15861d
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Price is $27.99
Unit of measure 100/Pack

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.