The singer will be joined by Jenny Frost and Liz McClarnon for a series of summer gigs, possibly including the Queen's Jubilee concert in June.
Rumours surfaced last month that the band, known for hits such as 'Whole Again' and 'Eternal Flame', were reforming when it was reported that they were in talks to star in a television show.
"We're really excited about getting back together and singing again. We've all been doing our own thing but we thought the time was right to reform. I think it will be fun to go on tour to perform for a whole new generation of fans," Hamilton told the Daily Star Sunday.
"A lot of our fans will have kids now so it would be great if they can both come along to watch us and enjoy our music. We'd love to be able to perform for the Queen's Jubilee celebrations. We're open to all options at the moment."
Hamilton also hinted that Kerry Katona, who formed part of the band's original lineup before quitting in 2000, could be part of the reunion plans.
"I ran into Kerry recently and we just hugged and got on really well. We both have kids around the same age so we talked a lot about them. It was lovely to see her. It would be great if we could all get on stage and sing together," she said.
Katona recently rehired Martin O'Shea, her agent from the Atomic Kitten days, after dumping Max Clifford.
Atomic Kitten were rumoured to be reforming for the Eurovision Song Contest, but they later denied the claims, and Engelbert Humperdinck was chosen to represent the UK.
> Kerry Katona teases Atomic Kitten reunion: 'We never fell out'
Watch Atomic Kitten in their video for 'Whole Again' below: