Since there are penalties for non-payment of estimated tax, and since you are self-employed, it is recommended that you file these taxes. They are due quarterly, as follows: April 15, June 15, September 15, and the following January 15. The total of these payments would be shown on your personal return 1040, page 2, as an offset against total tax. If you have high-volume income I think an S Corporation would work best.