Its decision to build the new police stations forms part of a cost saving plan, and will see the total number cut from 14 to six.
New buildings will be constructed at in Fareham, Hook, Winchester and Newport on the Isle of White, which will be financed from the sale of closed stations.
The authority met earlier this week to decide whether to lease the centres from the private sector or build new ones.
Designing and building the new centres will cost £67m over 30 years, compared to £86m if they were leased back from the private sector in a PFI deal, estimate the cost consultants.
Assistant Chief Constable David Pryde said: “Modernising custody and making the whole process more cost-effective is at the heart of this project.
“Being able to process criminals far more quickly and get them into court has got to be bad news for anyone who breaks the law.
“It’s true there will be fewer custody suites across the two counties, but the new builds give us the opportunity to update the system and make it more efficient as a whole.”