SIGs don't typically need insurance, but at a certain stage Chapters may deem it necessary.

General Liability insurance for your business typically will cover events that you do, but you must check with your insurance provider, ACBS endorses no particualr insurance carrier, and encourages each chapter to do its own due diligence.  

If your general liability policy doesn't cover events (or if you do not have a general liability policy) you can purchase event insurance to cover any events that you do. There is also "event cancellation insurance" that can protect you in case your event must be cancelled for some reason.One other insurance you may want (and ACBS has) is "D&O insurance", or "Directors & Officer's Insurance".  

This insurance protects your Directors and Board Members (Officers) from personal liability, if the organization is sued. If you have any regular, paid employees, you may need worker's compensation and other insurances.

One option for getting a quote on D & O insurance in the USA is here:  https://www.affinitynonprofits.com/

They can provide both general liability and D&O coverage, cost and coverage can vary but the San Fran Bay Area Chatper offered this information.  "We at the San Francisco Bay Area Chapter are wondering what has been others chapters' experience with Liability and D&O insurance. We are incorporated as a nonprofit and have been collecting dues and running workshop income and expenses through our books for less than 2 years. Activities are chapter meetings (mostly educational); social events; and trainings. The one quote we got so far was $1050 for Liability and $600 for D&O coverage".

SF Bay Area Chapter ended up with insurance through
Nonprofits Insurance Alliance
www.insurancefornonprofits.org

For premiums slightly less than mentioned earlier.