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Saturday: 8AM–8PM ET

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Costello & Sons Insurance (CSI) is a third generation brokerage with roots in downtown San Francisco. We have grown to over 2,000 clients and over $45,000,000 in premium, which puts us in the top 15% of brokers in the nation. With offices in Northern and Southern California, CSI is a regional insurance broker that is small enough to know its clients by name and large enough to insure clients with worldwide operations.

While most insurance brokers are “generalists” who attempt to be all things to all people, CSI specializes in two distinct groups:

1. Private Client Group
• Home, Auto, Umbrella, Life
2. Innovation Group
• Technology Companies
• Venture Capital & Private Equity

What makes us successful in each of our niches is the fact that:
• We represent every major insurance carrier in each niche
• We have personal relationships with these carriers due to our volume of business

Recently CSI was named one of the “25” Most Innovative Insurance Agents in the U.S. out of 26,000 existing insurance agencies. CSI is paperless, which not only contributes to our Green Business Certification, but it also allows us to provide up to the minute service for our clients.

Our Office:

Lincoln Avenue
San Rafael, California 94903

T: +1 415-257-2110
F: +1 415-455-1516


Michael Wardenburg, Senior Vice President