The Mean Girls star checked out of Cliffside Malibu Rehab Centre in California on Tuesday (30 July), according to reports.
Lindsay, 27, was photographed leaving the facility looking healthy and happy, wearing a short flower patterned dress and ankle boots.
She hasn't said anything on Twitter about leaving rehab but did appear to be alluding to the pictures when she tweeted: "They spotted me! @spottedfriend #repéré."
According to TMZ, the actress will now stay with a sober coach in Los Angeles for a few days as she adjusts to post-rehab life.
Lindsay avoided possible jail time earlier this year by accepting a plea deal in March over charges stemming from a car crash in Santa Monica last year. She was sentenced to 90 days in a locked-down rehab facility, 30 days of community labour and 18 months of psychotherapy, along with fees.
She later described the rehab sentence as a blessing, saying: "I'm the happiest and healthiest when I'm working and I think this is an opportunity for me to focus on what I love in life. I don't think it's a bad thing, I think it's a blessing, not a curse."
Her post-rehab plans will include an eight-part reality series for Oprah Winfrey's OWN cable network and an interview with the media mogul.
She'll also guest host an episode of E!'s Chelsea Lately on Monday, 5 August and has been receiving good reviews for her performance in new movie The Canyons, filmed before her rehab stint.
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