Royal & SunAlliance is the latest insurer to offer its products via imarket in conjunction with software company Acturis.
Enterprise Shops is the first suite of products available, while Enterprise Offices is scheduled to be introduced in the first quarter of 2006.
Simon Cooter, director of small business and e-business at RSA, said the insurer is working with other major software houses with imarket, but declined to name them. He added: "I expect a stream of activity from imarket players in the coming weeks".
According to an Acturis spokesperson, Enterprise Shops has already been rolled out to 29 brokers and is available to other Acturis/RSA users.
RSA is monitoring four brokers closely for several weeks in order to ensure the new system is working and to gather feedback from users.
Cooter said brokers will be able to access RSA's Business Partner Extranet via imarket. This offers more than 400 services including claims tracking and risk-management advice.
There are now four insurers offering shops on imarket over Acturis, including Groupama, Norwich Union and Allianz Cornhill.
Cooter added he expected any cost savings of imarket for insurers to benefit customers in the future.