Expanding Contracting Opportunities for Small Businesses Act of 2019 This bill modifies provisions regarding the inclusion of option years in the award price for certain sole source contracts (i.e., contracts awarded without a competitive process) by requiring the base and each of the option years of the award, if any, to be of similar value. Under current law, option years in the award price for such contracts limit their dollar award threshold. Specifically, the bill revises requirements for the award of these contracts to (1) qualified Historically Underutilized Business Zone (HUBZone) small businesses, (2) small businesses owned and controlled by service-disabled veterans, (3) economically disadvantaged small businesses owned and controlled by women, (4) small businesses owned and controlled by women in substantially underrepresented industries, and (5) qualified socially and economically disadvantaged small businesses. The Government Accountability Office must evaluate the policies and practices used by the Small Business Administration and other federal agencies to ensure that contracting officers are properly classifying sole source contracts under procurement programs for businesses owned by women and disabled veterans in the Federal Procurement Data System.