Insurer takes on Manchester and Basingstoke portfolio.
RSA has acquired the renewal rights for insurer Navigators regional marine and engineering portfolio, worth £4m GWP.
In a statement the insurer said the deal was concluded in June following Navigators' announcement that it was withdrawing from the market following a strategic review.
RSA is the UK's largest marine insurer and take over Navigators' regional portfolio consisting of approximately 1200 clients.
Barry McConway, director for Marine at RSA, said: "We are delighted that we have been able to take on the renewal rights of this portfolio.
"It will enable us to demonstrate our technical ability and appetite to service this type of portfolio and provide a clear message to the marketplace that we are ready and able to seize this type of opportunity.
"We look forward to building long term relationships with these brokers and welcome other brokers to contact us regarding similar business."