There are five basic paper grades:

Old Corrugated Containers (OCC), also known as corrugated cardboard.

Mixed paper: Mixed paper is a broad category that often includes items such as discarded mail, telephone books, paperboard, magazines, and catalogs. Mills use mixed paper to produce paperboard and tissue, as a secondary fiber in the production of new paper, or as a raw material in non-paper product such as gypsum wallboard, chipboard, roofing felt, cellulose insulation, and molded pulp products such as egg cartons.

Old Newspapers(ONP): primarily use old newspapers to make new recycled-content newsprint and in recycled paperboard and tissue, among other paper grades.

High Grade Deinked Paper: This grade is made of high grade paper such as letterhead, copier paper, envelopes, and printer and convertor scrap that has gone through the printing process. It must first be deinked before it can be reprocessed into high grade paper products such as printing and writing papers or tissue.

Pulp substitutes: A high grade paper, pulp substitutes are often shavings and clippings from converting operations at paper mills and print shops.