Formal Friday is a tongue-in-cheek reference to Casual Friday

Casual Friday

Casual Friday along with dressing casually during the week became very prevalent during the Dot-com bubble of the late 1990s and early 2000s rooted in a relaxed California-based business culture...

 and a reaction to the continuing trend towards casual workplace attire. On Formal Fridays, employees at companies with otherwise lax dress codes dress up in formal wear

Formal wear

Formal wear and formal dress are the general terms for clothing suitable for formal social events, such as a wedding, formal garden party or dinner, débutante cotillion, dance, or race...

. The practice is particularly common among technology companies. Examples include Last fm

Last.fm

Last.fm is a music website, founded in the United Kingdom in 2002. It has claimed 30 million active users in March 2009. On 30 May 2007, CBS Interactive acquired Last.fm for UK£140m ....

, Clearspring

Clearspring

Clearspring Technologies is a web technology company based in McLean, Virginia, USA. Clearspring's AddThis sharing platform reaches 1.2B unique visitors monthly and is used by over 10MM web publishers to virally distribute and track content across blogs, social networks and other web sites...

and Microsoft.

Rules for Formal Friday

Formal Fridays fall on Fridays in which the day of the month begins with an F in the English language. For example, Friday, November Fourth is a Formal Friday, as is Friday, July Fifteenth. This creates an irregular pattern to Formal Fridays, which is part of the appeal.

Future Formal Fridays

* Fri May 4, 2012
* Fri Jun 01, 2012
* Fri Jun 15, 2012
* Fri Sep 14, 2012
* Fri Oct 05, 2012
* Fri Dec 14, 2012
* Fri Jan 04, 2013
* Fri Feb 01, 2013
* Fri Feb 15, 2013
* Fri Mar 01, 2013
* Fri Mar 15, 2013
* Fri Apr 05, 2013
* Fri Jun 14, 2013
* Fri Jul 05, 2013
* Fri Oct 04, 2013
* Fri Nov 01, 2013
* Fri Nov 15, 2013
* Fri Feb 14, 2014
* Fri Mar 14, 2014
* Fri Apr 04, 2014
* Fri Jul 04, 2014
* Fri Aug 01, 2014
* Fri Aug 15, 2014
* Fri Sep 05, 2014
* Fri Nov 14, 2014
* Fri Dec 05, 2014
* Fri May 1, 2015
* Fri May 15, 2015
* Fri Jun 05, 2015
* Fri Aug 14, 2015
* Fri Sep 04, 2015
* Fri Dec 04, 2015

Alternatives to Formal Friday

The Formal Friday concept has arisen independently among many groups, sometimes called Fancy Friday. Homegrown campaigns have sometimes used different rules for when Formal Fridays occur. For example, on the second Friday of every month or even every Friday.