Facebook has been very patient since paying over $19 billion to acquire popular messaging app WhatsApp in 2014.

When it bought the then-5-year-old company, WhatsApp had about 500 million users, which Facebook has since tripled to about 1.5 billion. A significant chunk of the humans on earth use WhatsApp, so from that perspective WhatsApp has been a rousing success and great acquisition for Facebook.

WhatsApp is used by people around the world for everything from simple messaging, to running carpools and sports teams, to planning surprise parties, to running entire organizations. It is one of those few social media apps used by entire cross-sections of humanity – kids, teens, adults, corporates…. It has even become one of the few brands in the world to be turned into a verb – how often have you said lately in response to a request for a number or other piece of info, “I’ll WhatsApp it to you”?

One of the reasons for WhatsApp’s popularity and growth was its lack of intrusive ads. Great for the users, but also great for Facebook?

But when one of my kids – a serial groups creator and avid WhatsApp user, not to mention a budding entrepreneur – asked me recently how WhatsApp makes money, I had to think for a minute before saying, “I don’t know”. So after “Googling it” (another rare brand-verb), I came across Facebook’s own disclosure where the company basically admits it isn’t making much if any revenue from WhatsApp. Yet.

In its latest 10-K annual filing, Facebook states, “We generate substantially all of our revenue from advertising. Our advertising revenue is generated by displaying ad products on Facebook, Instagram, Messenger, and third-party affiliated websites….”. Most interesting from that statement is what is missing from it – WhatsApp. No revenue from there.

But today that seems to be changing.

WhatsApp has posted a blog indicating that it is launching payments to WhatsApp for people and small businesses, starting with Brazil.

Even the great Mark Zuckerberg himself took to his Facebook platform to post about the launch, saying that they’re planning on making sending and receiving money as easy as sharing photos. WhatsApp will also be enabling small businesses to make sales right within the app.

The WhatsApp digital payments service will be building on the existing Facebook Pay infrastructure, which the company set up to provide a secure and consistent way to make payments across its various apps – mainly Facebook itself and Instagram.

For the Brazil launch the company will be working with local banks, including Banco do Brasil, Nubank, Sicredi as well as Cielo, the leading payments processor for merchants in Brazil. To use the service, a WhatsApp user needs to add a supported debit or debit-enabled combo card to send or receive money. Users can utilize a supported debit or credit card to make payments to local businesses, or each other.

The plan is obviously to roll WhatsApp payments out around the world, following the Brazil trial.

Will this become the great and long-waited-for monetization of WhatsApp, without having to disturb the ad-free WhatsApp experience which has made the app so popular?

More on the initial WhatsApp payments launch can be found here.