Facebook just announced that it is acquiring WhatsApp for approximately $16 billion, including $4 billion in cash and approximately $12 billion in Facebook shares. The deal also includes an additional $3 billion in restricted stock units bringing the total to $19 billion.

The service has over 450 million monthly users with 70% active on a given day, according to the company. More impressive still is that (again, according to the company) messaging volume is approaching the entire global telecom SMS volume, and it’s still rapidly growing. It’s currently adding over a million new users per day.

Mark Zuckerberg said, “WhatsApp is on a path to connect 1 billion people. The services that reach that milestone are all incredibly valuable. I’ve known Jan for a long time and I’m excited to partner with him and his team to make the world more open and connected.”

WhatsApp co-founder and CEO Jan Koum added, “WhatsApp’s extremely high user engagement and rapid growth are driven by the simple, powerful and instantaneous messaging capabilities we provide. We’re excited and honored to partner with Mark and Facebook as we continue to bring our product to more people around the world.”

On the company blog, WhatsApp says:

Here’s what will change for you, our users: nothing.

WhatsApp will remain autonomous and operate independently. You can continue to enjoy the service for a nominal fee. You can continue to use WhatsApp no matter where in the world you are, or what smartphone you’re using. And you can still count on absolutely no ads interrupting your communication. There would have been no partnership between our two companies if we had to compromise on the core principles that will always define our company, our vision and our product.

On a personal note, Brian and I couldn’t be more proud to be part of a small team of people who, in just under five years, built a communication service that now supports over 450 million monthly active users worldwide and over 320 million daily active users. They have helped re-define and revolutionize communication for the 21st century, and we couldn’t be more grateful.

Our team has always believed that neither cost and distance should ever prevent people from connecting with their friends and loved ones, and won’t rest until everyone, everywhere is empowered with that opportunity. We want to thank all of our users and everybody in our lives for making this next chapter possible, and for joining us as we continue on this very special journey.

I’m guessing Facebook is no longer worried about acquiring SnapChat. Something tells me those guys will regret not selling.

Here’s the regulatory filing.

Image via iTunes