You may or may not; it simply depends on your jurisdiction. In Alexandria, just about every business needs a business license. However, you may not have to pay a business license tax if your company is small and makes under a certain amount of money annually. The obligation to obtain a business license is a serious issue. In fact, if you operate your company without the required business license, you may be committing a crime.
Some cities and counties in Virginia only require a business license if your company reaches a threshold amount of annual gross revenues. Therefore, it is important that you look into your jurisdiction or contact a small business lawyer who can provide you with more information.