#10 Window Envelopes - Single Window, Laser-Safe

#10 window envelopes are designed for standard 8.5 x 11 inch documents folded in thirds (tri-fold). This is the most common business letter format and works perfectly with invoices, statements, letters, and other business correspondence. The envelope dimensions are 4 1/8 x 9 1/2 inches, making them the standard business envelope size.

Yes! Our #10 window envelopes feature a laser-safe window that's compatible with all standard laser printers, inkjet printers, and copiers. The window position is optimized for standard business document formats, including QuickBooks invoices, Xero, FreshBooks, and most accounting software. Simply print your documents, fold them in thirds, and the recipient address will show perfectly through the window.

Peel & seal envelopes feature a self-adhesive strip—simply remove the protective strip and press to seal. They're faster and more convenient for high-volume mailing. Gum seal (also called moistening seal) requires moisture to activate the adhesive, offering a traditional, professional finish. Both seal types are equally secure. Choose peel & seal for convenience or gum seal if you prefer the classic approach.

The single window is positioned to align with standard business document address blocks. When you fold an 8.5 x 11" document in thirds, the recipient's address (typically positioned 2-4 inches from the top of your document) will show through the window. This works with most invoicing software, accounting programs, and standard business letter templates without any special formatting.

While these window envelopes work fine for checks, we recommend our #10 Security Envelopes (no window) for checks and confidential documents. Those feature security tint patterns that prevent readability when held up to light, providing better protection for sensitive information. However, if you need to mail invoices or statements along with checks, these window envelopes are perfect for that purpose.