The new contract will have the company take over lottery marketing, sales and distribution services.
The state received $188 million in lottery proceeds last year.
Officials expect the new deal with GTECH will increase profits by about $500 million over the first five years of the 15-year contract, said Karl Browning, the Hoosier Lottery's executive director.
"I can't find a scenario in which no matter what, the taxpayer isn't better off," Browning said.
GTECH was selected over a proposal from New York-based Scientific Games, which currently provides the central online lottery system, terminals and instant tickets for the Hoosier Lottery.
Private companies already handle 88 percent of lottery operations and the outsourcing proposal would increase that to 95 percent, Browning said last week. Indiana would retain full ownership and control of the lottery, he said.
Browning has said part of the increased revenue would come from a plan to "broaden the player base."