National Australia Bank Asset Servicing (NAS) has been appointed to provide custodial services to RAC Insurance.
The appointment is effective from 1 December and follows a three-month tender process.
The companies have not disclosed any financial details of the transaction.
RAC Insurance said the key factors influencing the choice of NAS were the ability to transition the company's assets within a short timeframe, the backing of National Australia Bank and the company's track record in the insurance market.
The custody needs of RAC Insurance were previously provided by Suncorp as part of a joint venture.
But after the end of the joint venture in 2008, RAC Insurance needed to appoint a new master custodian.
RAC Insurance is a regional insurer operating exclusively in Western Australia, specialising in motor and householder insurance.
The contract is the first custody contract the roadside assistance and insurance firm has awarded.
