Tax Form Management has a tool to find employer codes on its website, w2express.com. From the homepage, select the Find employer name link on the right sidebar. This opens another page that contains a list of employer codes.
The Find employer name page on w2express.com has a search box where you can type in an employer name to find the code for that employer. There is also an option to browse the entire list of codes. Select an alphabet letter or a number to view a list of employers whose names begin with that letter or number. The list displays the employer code next to each name.