Joe Rossignol, MacRumors:

If you own a 15-inch MacBook Pro with Retina display released in Mid 2012 or Early 2013, and your notebook qualifies for battery service, the repair should be free if you are willing to wait for around one month.

To check if your MacBook Pro battery needs service:

Click on the Apple logo in the menu bar. Then, click on About This Mac > System Report > Power. In the Health Information section, the condition should say “Service Battery.”

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