Lincolnshire Police have extended their appeal to find 15-year-old Daisy Dale from the Thornton le Fen area near Boston.
Daisy was reported missing by her foster mother on Tuesday, June 30.
She has been missing before, but it is understood that she usually returns after a couple of days. She has been known to travel to Boston.
A week on since her disappearance officers are urging people to consider the wider county area as the search continues.
Daisy was last seen wearing white trainers, dark blue skinny jeans and a white high neck fitted top with a tasseled waistcoat and carrying a big rucksack. She is about 5’ 5” tall.
Insp Whyment said: “We are obviously still very concerned for Daisy. We want her to get in touch with us to let us know she is safe.
“If anyone has seen Daisy or had contact with her, for instance through a social media account, please call us on 101 with that information.”
Anyone with any information on Daisy’s whereabouts is asked to contact police on 101 quoting incident number 224 of June 30.