Straus is self-employed in insurance and investments.

He and his wife’s stock listings include brand names like Comcast, Walt Disney Co., Lowes, Netflix, Time Warner, Whirlpool, Archer-Daniels Midland Co., Wal-Mart Stores, Chevron Corp., Exxon Mobil Corp., 3M Co., Fedex Corp., Tyson Foods, AT&T, Verizon Communications, United Health Group and Novo-Nordisk A/S Sponsored ADR. They also own a number of stocks — some of the same — in the names of their two daughters. 

He reported investment income from Frost National Bank, Plains Capital Bank, Broadway Bank, Charles Schwab & Co. and several San Antonio-based outfits, including Medina Investments, Peden Street Partners, Strafkids Realty Co., Moonbeam Ventures LTD JLS LLC and PTRX Marketing LLC of New Braunfels. 

He owns interests in Watson, Mazur, Bennett & Straus LLC, the Straus 2003 Irrevocable Trust and the Joe R. Straus Jr. Canyon Lake Trust of 2000.

Residence in San Antonio valued at $824,410

Straus' family has strong ties to horse racing, primarily through his father's holdings, and the Legislature regularly takes up legislation that would allow slot machines at race tracks. Straus has no apparent direct interests in any tracks. In the past, Straus has recused himself from voting on gambling issues.

In 2007, as a member of the House, Straus authored and helped pass a bill eliminating the Telecommunications Infrastructure Fund tax, taking $200 million out of the state's income and benefiting AT&T, his biggest campaign contributor. At the time, AT&T was headquartered in San Antonio. Straus called the measure a move toward more budget transparency; the fund had already reached its statutory cap.