Along with this, Twitter is also rolling out more granular controls so users can decide - to an extent - whether and how they want to be tracked and targeted.
The move comes as the company reels from its first quarterly revenue drop since going public and struggles to attract more users.
Twitter said Thursday that its new policy, effective June 18, also removes the "Do Not Track" option that let people opt out of being tracked by the likes of ad and social networks. Many such networks no longer honor that option anyway.
Users in Europe will be able to retain more of their privacy.