
9×12 Flat Mailer Envelope
The 9×12 flat mailer envelope ships documents, flyers, and multi-page inserts completely unfolded, which matters when a fold line would crease a photo, cut through a headline, or make a legal document look less official.
Bulk pricing from $0.55–$0.95 / unit at MOQ — final quote depends on quantity, print method, and options.
Get a Custom Quote| Material | Heavyweight white wove or kraft paper stock |
| Dimensions | 9″ x 12″ flat format |
| Color/Finish Options | White, Kraft Brown, Manila, Grey, Not sure yet |
| Decoration | Full-color offset printed or digitally printed |
| Decoration Area | Full front and back |
| MOQ | 500 units |
| Lead Time | 2 weeks |
| Packaging | Bulk-cartoned, ready for insertion or mail house drop-off |
About the 9×12 Flat Mailer Envelope
The 9×12 flat mailer envelope ships documents, flyers, and multi-page inserts completely unfolded, which matters when a fold line would crease a photo, cut through a headline, or make a legal document look less official. It’s the format law firms use for engagement letters and case documents, the format real estate brokerages use for full-page property brochures, and the format nonprofits use when an appeal letter needs to arrive looking like a formal, considered piece of mail rather than a mass-produced flyer. We print full color on both the front and back, so a cover design, return address, and any teaser messaging on the reverse all print in register and in vivid color. Because the format is larger, we build in extra care in production to keep boxes flat and unbent through fulfillment and shipping to your mail house or directly to the post office. Bulk orders start at 500 units and scale to tens of thousands for large campaigns; larger flat mailers like this one benefit especially from volume pricing since paper and press setup costs amortize across a bigger run. Typical order scenarios include a law firm mailing an unfolded contract or engagement package, a real estate brokerage sending a full property brochure to a targeted buyer list, a corporate HR department mailing benefits enrollment packets, and a political campaign sending an unfolded policy one-pager ahead of an election. Because 9×12 mailers are heavier and bulkier than a #10 or 6×9, postage costs run higher — we’ll factor accurate postage into your quote so there are no surprises once your mailing is ready to drop.
Built For
Law Firms & Professional Services: Unfolded engagement letters and case documents that read as formal and considered.
Real Estate: Full-page property brochures mailed flat, without a crease across the photography.
Nonprofits & Fundraising: Formal, unfolded appeal packages for major-donor and year-end campaigns.
FAQ
Will my documents arrive without creases?
Yes — the 9×12 format ships flat and unfolded by design, protecting photography and print layout.
Can this handle a heavier insert like a booklet?
Yes, ask us about your specific insert weight so we can confirm paper stock and postage.
Do you offer a rigid or reinforced version?
Ask on your quote if you need extra rigidity for photography or presentation materials.