Nine constructions, one process. Every line here is manufactured to the specification you give us (stock, size, pocket layout and finish) and every one includes a free proof before production. Filter by what the folder has to do.

The standard two-pocket folder. Scored cover, glued pockets, holds a stack of letter-size handouts.

Premium cover stock and finish for pitches, proposals and client meetings.

Sized for legal-length paper and oversized documents, nothing folded to fit.

Your size, pocket layout and finish. Built around what you actually need to hold.

Corner or ribbon-style slits hold a diploma or award flat, without adhesive.

A reinforced-tab office folder that puts your logo on every file that crosses a desk.

Sized to match print dimensions. The handoff folder for portrait and event photographers.

A standard folder cut into a custom shape: rounded corner, notch, or your logo's outline.

A third panel and extra fold for kits that need more than two pockets' worth of space.
Start with what the folder has to hold, not how it looks. A branded handout going to a room full of people is a volume decision. Standard pocket, 10-12pt, done. A folder handed across a table once, deliberately, at the close of a pitch, is doing a different job and can carry a premium presentation-grade finish.
If the contents are legal-length or otherwise won't fit a standard 9"×12" pocket, legal is the only construction built for that. Don't force an oversized document into a standard folder. If the folder needs to protect a single certificate or print rather than a stack of papers, certificate and photo folders use a slit instead of a pocket, which holds a single piece flat without it sliding around. And if nothing standard fits the project. An unusual size, a shaped die-cut, a three-panel layout for a multi-piece kit, that's exactly what custom, die-cut and tri panel exist for.