OSGroup in Windham, NH, offers a complete suite of services for businesses and individuals that you would expect from a reputable CPA firm audit services, tax services, and accounting support but we are proud to say that we take our role a step further. Our goal is for you to be able to rely on us to be a part of your team of strategic business advisors, helping you through the difficult decisions you face day-to-day and week-to-week in managing and growing your business.