Sirius has become the seventh software house to agree terms to join Polaris's online trading platform, imarket.
The software house concluded negotiations with Polaris last week and will now join its six main competitors in developing connectivity to the portal.
Sirius chief executive, UK Systems Mike Dodd said: "We think we have struck the right deal for ourselves and our customers."
Polaris marketing and strategy manager Phil Nunn added: "It is good to have Sirius on board. They have good clients and are well advanced on their commercial side.
"This step will allow us to focus on integration planning for each software house."
All the major software providers - Misys, SSP, CDL, Sectornet, Acturis, insurE-com and Sirius - have agreed terms.
Polaris is now looking to integrate the systems of smaller niche players or in-house systems.
Nunn said: "We are very keen to speak to further software houses and brokers with their own systems."
Polaris has also extended the roll-out of its schemes library, increasing the number of products from 20 to 50.
The system is designed to allow brokers to search through a list of specific products. A selected product is then linked through to insurer or brokers websites. It is due to be launched in December.
Nunn said: "We are ahead of schedule.
"We now have over 1200 brokers registered with imarket and the number of transactions per month is constantly rising."
