"This morning, there are more than one billion people using Facebook actively each month," said Mark Zuckerberg, the Co-founder and CEO of the social media giant.
"If you're reading this: thank you for giving me and my little team the honour of serving you. Helping a billion people connect is amazing, humbling and by far the thing I am most proud of in my life."
Topping the one billion mark means that Facebook now reaches one out of every 7 people on the planet, CNN reported, adding that the site has a presence in more than 200 sovereign territories.
The California-based company said those billion users were to date responsible for 1.13 trillion 'likes', 219 billion photos and 17 billion location check-ins.
It took Facebook, launched in 2004, six years to hit the 500 million user mark and barely two to double it.