The Health Ministry says it expects up to 90 percent of children aged six to 12 will receive free doctors' visits from July.
Children under the age of six already have free GP visits, and the Government pledged to extend this to 13 in the Budget last May.
Ministry deputy director-general Cathy O'Malley told Parliament's health select committee that negotiations with GP practices, pharmacies and ACC over extending the policy had gone well, and a subsidy had been agreed.
She said when free visits for under sixes was rolled out, it took time for GP practices to come on board, but now 99 percent of children under six who are enrolled with a practice have free visits, with a similar proportion also getting free after-hours visits.
Ms O'Malley said the same should occur this time.