When most people think of wills and estate plans, they usually think about the primary function of distributing assets to children. The natural next thought is, if they have no children, then they don't need a will. But estate plans, and especially wills, actually serve a number of important purposes, only one of which is conveying assets to children.
As U.S. News & World Report points out in, "No Kids? You Still Need an Estate Plan," people without children need, at the very least, to have a will if they want to have a say in who gets their assets after they pass away.
People who pass away without a will are said to have died intestate. Every state has a law that determines who gets the assets of people who die intestate. The laws all operate similarly, in that the assets are given to the person's closest living relatives.
Under such law, those who have a spouse or children will have their assets given to that spouse or the children. If however you have no spouse or children, then your assets will be distributed to other relatives, depending on who is closest in line. Ultimately, if you have no living relatives that can be found, then the assets will be claimed by the government. The term for this is escheat.
So, the primary purpose of estate planning for most people is avoiding the laws of intestacy and deciding for yourself who will inherit from you.
Do not let the fact that you do not have children deter you from getting an estate plan. Contact a qualified estate planning attorney to help you design a custom plan for your unique circumstances.
Reference: U.S. News & World Report (October 14, 2015) "No Kids? You Still Need an Estate Plan"