Twitter’s global reach is likely a defining factor in why the top businesses in the UK prefer Twitter over Facebook. Out of the top 100 most highly capitalized UK companies on the London Stock Exchange (also known as the FTSE 100), 63 choose to use Twitter as part of their social media strategy, while only 33 have a Facebook page.

Figures from the FTSE social media study from Threepipe Communications tell an interesting story about how some of the most profitable companies in the world choose to use social media.

Twitter is by far the most popular social networking tool among the UK corporate elite. Among the 63 firms that use Twitter, several use it to share their annual results (Aviva and Rio Tinto), 11 use it for customer service and help desk functions, and six use it to raise brand awareness for their social responsibility endeavors.

Interesting tidbit: pharmaceuticals heavy-weight GlaxoSmithKlein was the first FTSE 100 company to join twitter, sending out their first tweet in April of 2007.

Several of the FTSE 100 have multiple Twitter accounts – one even has as many as 32. And how they use Twitter, and the results they see, varies greatly: some of the FTSE tweet quite regularly, even as often as once per hour, and others see retweet rates as high as 50 times per tweet. However, only 14 of the FTSE 100 offer a link to either their Facebook or Twitter presence from their official corporate website, indicating that there is still a ways to go when it comes to social media among the big boys.

You can view the study here [PDF], or take a look at the below infographic which sums up the findings: