Carterton councillors are unhappy that Carterton residents have to pay to use Masterton Library services but Masterton residents can use Carterton Library services for free.
At a Carterton District Council meeting last week, community development manager Lorraine Gittings said Masterton was worried it would end up costing them more if their library services were free for Carterton residents.
"I think one of the biggest issues is the concern that Masterton will end up carrying a wider share of the costs," she said.
Ms Gittings said a three or six-month trial has been suggested to see what the flow is.
"We certainly get a lot of Masterton customers using our library.