Small Business Size Regulations specifying size standards and governing their use are set forth in Title 13, Code of Federal Regulations, part 121 (13 CFR §121).  SBA's size regulations pertaining to Federal procurement are also found in the Federal Acquisition Regulation, 48 CFR part 19.

The Electronic Code of Federal Regulations (eCFR) is maintained by the U.S. National Archives and Records Administration. It includes all changes to the Small Business Size Regulations, which are current as of the date specified at the top of the linked page.

Information about any recent actions SBA has taken or has proposed to take regarding its size standards are listed in What's New.