Certified Mail Envelopes - Letter Size #10, Machinable
Sealed machinable window envelope with the green USPS Certified Mail band pre-printed.
Full-size sheet folds into thirds before insertion.
Starting at $22.45
Add to CartCERTIFIED MAIL ENVELOPES & MAILING SUPPLIES
Buy Certified Mail Envelopes & Mailing Supplies Online
Order official Certified Mail envelopes, labels and mailing supplies online, or let us print, stuff and mail your letter the same business day. No trip to the Post Office, ever.
No monthly fees. No contracts. No equipment leases.
Shop the essentials
Shop envelopes & supplies
Order the exact envelope or label you need, in the quantity you need, and check out online.
Certified Mail Envelopes - Booklet 6x9, Machinable
Machinable booklet size for thicker legal, compliance and document sets.
Starting at $24.45
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Certified Mail Envelopes - Flat 9x12, Machinable
Machinable flat size for multi-page filings and large document packets.
Starting at $29.45
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First Class Envelopes - Letter Size #10, Machinable
Plain machinable first class window envelopes for standard business mail.
Starting at $26.00
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First Class Envelopes - Booklet 6x9, Machinable
Plain machinable first class booklet envelopes for larger mailings.
Starting at $22.00
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First Class Envelopes - Flat 9x12, Machinable
Plain machinable first class flat envelopes for oversized documents.
Starting at $43.00
Add to CartSend Certified Mail - We print and mail the same business day!
Upload a PDF and address list and we print, stuff, apply postage and mail the same business day for orders received before 5:00 PM Eastern on a USPS business day. Orders after the cutoff, on weekends, USPS holidays or needing file or address corrections mail the next business day. Every mailing includes a notarized affidavit of mailing, USPS acceptance, tracking and delivery records in a searchable 10-year archive.
A better mailing desk
The details are the point.
When a deadline, audit, or dispute depends on a mailing, small gaps become big problems. We close them before the envelope leaves.
01
Skip the counter
Create live-postage Certified Mail labels and print them at your desk—on regular paper, window envelopes, or adhesive labels.
02
Keep proof in reach
Every mailing can include USPS acceptance, tracking, and delivery events in one searchable archive. Return Receipt Electronic is an optional add-on for a recipient signature; USPS publishes events as it processes the piece, so records appear over time.
03
Move today's work today
Send us a PDF and address list before 5:00 PM Eastern and we can print, stuff, postage, and mail the same business day.
Same-business-day mailing applies to orders received before 5:00 PM Eastern on a USPS business day. Orders received after the cutoff, on weekends or USPS holidays, or that need file or address corrections, mail the next business day. All mailing dates depend on USPS acceptance.
04
Scale without contracts
Automate high-volume mail with Excel, CSV, API, or secure SFTP workflows—without monthly fees or equipment leases.
For the work that needs receipts
A mailing service that remembers.
From a single legal notice to a national compliance campaign, Certified Mail Envelopes gives your team a straightforward way to send with confidence and find the record ten years later.
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