Atlanta airport general manager Roosevelt Council said Clear will not displace the PreCheck lines, but will be alongside PreCheck.
Clear CEO Caryn Seidman Becker said in a written statement: "The expansion to ATL has been in the works for some time and is one of many major airports we will be opening in the coming weeks and months."
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Clear opened lanes at New York's LaGuardia Airport on Wednesday and at John F. Kennedy International in late December, and plans to expand to Los Angeles International and Minneapolis-St. Paul in the first quarter of this year.
The Clear kiosks are near the Delta Air Lines check-in area. Clear is partnering with Atlanta-based Delta to launch the service at Delta's hubs.
Delta originally planned to launch Clear lines at its hubs last summer, but the rollout has taken longer than expected, with Clear lines gradually launching at airports around the country.
So far, Clear is at more than a dozen airports nationally, including Dallas/Fort Worth, Denver, Las Vegas, Miami, Orlando, San Francisco, both Washington, D.C. airports and both Houston airports.
A one-year Clear membership costs $179. That's significantly more than TSA PreCheck membership for expedited screening, which costs $85 for five years.
Delta is offering discounted Clear memberships to its SkyMiles frequent fliers, including $99 annually for general SkyMiles members and $79 annually for platinum, gold and silver level elite SkyMiles members. Delta's diamond-level elite SkyMiles members can get Clear membership for free.
Clear says it is integrated with PreCheck and is "the fastest, most predictable way through airport security."
Delta CEO Ed Bastian said last year that "with Clear, customers can go directly to the front of the TSA PreCheck queue." The airline also bought a 5 percent stake in Clear, Bastian said.
A previous company launched Clear registered traveler security lines in 2005, but that service failed in 2009.
The new version of Clear is run by a different company, which says on its website that it will honor any remaining time that members of the old Clear have on their accounts.