TWO teenage schoolgirls who went missing from Sydney's northwest have been found safe and well.

Teagan Lloyd and Skye Keenan, both 13, went to school in Rouse Hill on Wednesday morning but left around lunchtime.

Their mothers made tearful pleas for their daughters to return home on Saturday.

The two girls were found at Chatswood railway station about midday on Sunday, a police spokeswoman said.

A member of the public had contacted police after recognising the girls on CCTV footage released to the media.

A police spokeswoman told AAP officers went straight to Chatswood station following the call and the girls were now in police care.

Police had tracked the pair to a home in the Mount Druitt area about 4am (AEDT) on Friday and learned they had then caught a train from St Marys about 9am on Friday to Parramatta.

In public appeals on Saturday, Teagan's mother Lisa Lloyd said: "We desperately miss you and love you. There is no trouble. We just need to hear from either of you.

"We are looking for you, we just need you to come home."

Skye's mother Gina Keenan said they hadn't slept.

"We have been looking everywhere. Everyone is looking for you, everyone misses you. You are not in trouble, we love you."

Police monitored social network sites and interviewed Year 7 students at the girls' school, as well as their teachers.

Police on Sunday thanked the media and the public for their assistance in finding the girls.

Originally published as Missing Sydney teens found