The robbers, who wore masks and threatened staff with a knife, left the restaurant by foot at around 23.30, but were found half an hour later.
Using search dogs, police traced the teenagers to an apartment in east Halmstad.
They entered the apartment around midnight on Sunday and found three girls there aged 13, 14 and 16.
All three were arrested but the 13 and 14-year-old were soon released due to their young age. The 16-year-old, however, is being held on suspicion of robbery.
"We found robbery paraphernalia along the road between the restaurant and the apartment, like hoods and knives," police officer Jens Christensen told a local radio station.
He said the girls knew each other but did not want to comment on whether or not they were related or friends.
The stolen money was found hidden below one of the apartment windows.
Police have notified the girls' parents and social services.
TT/The Local/nr Follow The Local on Twitter