Companies will also be able to link to their WhatsApp chat from their websites or pay Facebook for an ad to promote the chats.
In an online post on Wednesday, Facebook said: "We're introducing a solution for businesses that require more powerful tools to chat on WhatsApp and a new way for people to quickly start a WhatsApp conversation from an ad on Facebook."
In June, there was a hint that Facebook would look to profit off WhatsApp when the messy details of the break-up between the WhatsApp founders and Facebook were revealed.
WhatsApp co-founders Jan Koum and Brian Acton have made no secret of their distaste for invading people's privacy and also for advertising.
But Facebook's Mark Zuckerberg and his chief operating officer Sheryl Sandberg put pressure on Koum and Acton and finally the two left the company in disgust. Zuckerberg and Sandberg "grew impatient for a greater return on the company’s 2014 blockbuster US$22 billion purchase".
"Facebook Ads that click to WhatsApp help people discover your business, help you engage with them to explain your product or service and grow a relationship," the company said in Wednesday's post.
"You will continue to have full control over the messages you receive. Businesses will pay to send certain messages so they are selective and your chats don't get cluttered."
Facebook lost about US$120 billion of its value on 26 July after the company announced what was its slowest growth of users and warned that revenue would fall for the remainder of the year. Zuckerberg's personal fortune fell by almost US$16 billion.
The announcement was made at an earnings call for its second-quarter results. Facebook had revenue of US$13.23 billion, compared to US$9.32 billion during the corresponding quarter in the previous year. Net income for the quarter was US$5.1 billion, compared to US$3.89 billion in Q2 of 2017.