Recently, when we were planning the refresh of our website, we had to answer this question. We were developing a “solutions” section as part of the refresh; the section would contain pages dedicated to the materials we print most often. Since flier/flyer is one of our most frequently printed materials, we had to pick a way to properly spell it for the sake of consistency.
Traditionally, we have spelled it flier. However, there is always a communication or two where it appears as flyer. Deciding how to spell flier/flyer was made more difficult for us because in the Philadelphia area, an online search for “flyers” returns an awful lot of information about the local professional hockey team. We’d much rather appear in a search for flyers, the printed material.
To inform our discussion we turned to Grammar Girl, one our favorite resources on grammar. She just happened to have a post on the very question we were asking. According to Grammar Girl, flier had been the traditional American spelling for a handbill or piece of paper that contains information. Flyer was the commonly accepted British spelling. She cited sources such as the Associated Press and Garner’s Modern American Usage as defining flier as the proper usage in American English.
Unfortunately, things have changed during the last year or so. In an update to her original post, Grammar Girl said recent practice has swung in favor of flyer as the proper spelling in American English. This was made definitive when the Associated Press switched its accepted spelling to flyer in its 2017 Style Guide.
Relying on these respected sources, we decided to go with flyer as the spelling for the solutions section of our website. Flyer is also how we spell it in all our communications now. So, now you know.