She was last seen in the area at 11.30am on Wednesday (December 27).
Officers believe she may have caught a train from Stoke-on-Trent to Manchester Piccadilly on the same day.
Chelsea has mousey brown hair and was last seen wearing black ripped jeans, a grey Ellesse top and pink Nike trainers.
Police are currently working to find a more up-to-date picture of Chelsea, but officers still think someone could recognise her.
If you have any information about Chelsea's whereabouts, please get in touch.
You can call 101, quoting incident 476 of 27 December or message police using Live Chat on the Newcastle-under-Lyme Police website.
You can also call Crimestoppers anonymously on 0800 555 111.
