You can print Forms W-2 on plain 8-1/2" by 11" paper. When you print on plain paper, the employee's address is visible through a single-window, standard No. 10 business envelope (4-1/8" by 9-1/2", left-aligned window).
In most cases, you'll need two pages for each employee, with Copy B and the instructions on the first page, and the rest of the copies on the second page.
In special cases, some employees have more data and need more than two pages. For example, if an employee is subject to more than two local taxes, or has more than two items in Box 14, or more than four items in Box 12, we print additional copies of Form W-2 with just the additional data.
If you want to print on perforated paper instead, see Form W-2: Printing on perforated paper.
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