The British Insurance Brokers' Association (Biba) will subsume the Association of Intermediaries and Insurance Brokers (AIIB) in April.
The AIIB's 400 members have already been sent information and consultation packs on the proposed merger.
The consultation period will end on 31 January and an Extraordinary General Meeting will be held in either February or March so members can vote on the move.
AIIB chairman Mike Slack will join the main Biba board and the Biba General Insurance Brokers Committee, with responsibility for brokerages with up to 15 employees.
AIIB members will continue to pay membership fees at their existing rate until 1 January 2003, after which they will be brought in line with Biba's fees over the following two years.
The AIIB will be dissolved following the merger, with its remaining assets to be transferred to Biba.
