The group were at HMV in Glasgow's Buchanan Street to sign copies of 30 Days, their latest single.
The queue to see band members Una Healy. Mollie King, Frankie Sandford, Vanessa White and Rochelle Wiseman stretched from the store, along Sauchiehall Street to West Nile Street.
A group of friends at the front of the queue said they had been there since 4am and brought sleeping bags and blankets to keep warm until the band arrived at 5pm. Jodie Montgomery, 15, of King's Park and her friends, were "excited" to be there.
She said: "I love Mollie because she is so amazing."
Four-year-old Orlaith McCluskey rushed up to get her CD signed.
Mum Kirsten, 25, of Motherwell, said: "She loves The Saturdays and listens to their music all the time.
The band will play at the SECC on Sunday for In: Demand Live.
Emily Millar and Julie Marley, both 13, also met the band.
Emily said: "It was so exciting, they were just so nice." Julie added: "We are very big fans."
Ashley McCluskey, 14, from Drumchapel could hardly speak through tears of joy after meeting them.
She said: "They were even nicer than I expected."