9.75" x 12.5" Stay Flat Envelope

The 9.75 x 12.5 stay flat envelope gives 8.5 x 11 documents a touch more room than a standard 9 x 12 mailer, and that small margin matters when you are shipping thicker booklets, lookbooks, multi-page magazines or subscription box inserts. This 9.75 x 12.5 rigid mailer is built from 420 GSM heavy duty cardboard that refuses to bend, crease or buckle through carrier sorting machines, weather or rough handling. The white, label-ready finish takes ink, stamps and shipping labels cleanly.

Inside, the 9.71 by 12.46 inch cavity is sized to comfortably hold 8.5 x 11 paper, multi-page lookbooks, thicker magazines and thin catalogs with breathing room. The 1.97 inch flap folds back fully so you can load contents fast even when batches stack up, and the self-adhesive seal strip closes each 9.75 x 12.5 mailer in seconds without tape, scissors or extra tools. The built-in tear strip on the back gives recipients a clean opening, which keeps your unboxing experience consistent for ecommerce and subscription customers who notice these details.

This is the size to reach for when standard 9 x 12 mailers feel a bit tight: thicker lookbooks, catalog prints, magazine issues and subscription box inserts all fit better here. It also works for offices mailing thicker contract sets, photographers shipping 8 x 10 prints with multiple interleaf sheets, and Etsy or Shopify sellers mailing multi-piece art print sets. Every pack ships with 200 free Do Not Bend stickers, the cardboard is fully recyclable, and bulk packs of 50 or 100 bring the per mailer cost down for businesses shipping the 9.75 x 12.5 stay flat envelope on a regular schedule.

• Extra margin around 8.5 x 11 documents fits thicker booklets, lookbooks and magazines comfortably
• Heavy duty 420 GSM cardboard keeps contents perfectly flat through carrier handling
• 200 free Do Not Bend stickers included in every pack for carrier visibility
• Self-adhesive peel and seal strip closes each mailer in seconds, no tape needed
• Built-in tear strip on the back gives recipients a clean, damage-free unboxing

• Subscription box brands shipping lookbooks, magazines and oversized product inserts
• Magazine and catalog publishers mailing multi-page issues and seasonal catalogs
• Offices mailing thicker contract sets and signed agreement binders
• Photographers shipping 8 x 10 prints with multiple interleaf or protection sheets
• Etsy and Shopify sellers mailing multi-piece art print sets and poster bundles