Streaming giant Netflix Inc on Tuesday began its planned crackdown on password sharing in the United States, alerting users that their accounts cannot be shared for free with people outside of their households.

The streaming video pioneer has been looking for new ways to make money as it faces signs of market saturation, with efforts including the password crackdown and a new ad-supported service.

The company said it was emailing customers who have been sharing passwords to tell them they can add an extra member outside their homes for $8 per month.

They can also transfer a person's profile so the user can keep their viewing history and recommendations.

People within the same household can continue sharing the same Netflix account and can use it on various devices when traveling, the company said in a blog post.

Netflix announced last year that it was going to limit password sharing and had already tested various approaches in some markets.

(Reporting by Manya Saini in Bengaluru, editing by Deepa Babington)