The U.S. Small Business Administration (SBA or Agency) is amending its regulations to incorporate a provision of the National Defense Authorization Act of 2018 (NDAA 2018) and to update and provide several technical corrections to SBA's regulations. Specifically, the NDAA 2018 amended the Small Business Act by replacing fixed dollar amount thresholds with references to the micro-purchase and simplified acquisition thresholds. SBA is updating its regulations to conform to this new statutory language. SBA is also updating the sole source dollar amounts for the Service-Disabled Veteran-Owned (SDVO) small business and the Historically Underutilized Business Zone (HUBZone) small business regulations. The thresholds for sole source contracting are contained in the Small Business Act, SBA's regulations, and the Federal Acquisition Regulations (FAR). These thresholds are updated in the FAR for inflation periodically, and therefore, over time, SBA's regulations and the FAR's numbers diverge. SBA is making this change to conform the thresholds contained in SBA's regulations to those in the FAR. This rule also allows indirect ownership by United States citizens in the HUBZone program to more accurately align with the underlying statutory authority. Finally, SBA is making several technical changes to address mistakes and typos made in previous rulemakings. For example, this final rule will update some cross-references that were not updated when a previous rulemaking changed numbering. Other changes made are for errors, grammar, syntax, and clarity.