The Tax Cuts and Jobs Act (TCJA) eliminated the ability of a professional gambler to take a loss on his Schedule C based on his business expenses; Congress specifically overrode the Mayo v Commissioner decision. But what about state taxes? Can a professional gambler who had a losing year take a loss on those returns?
First, no professional gambler can take a loss based on his gambling results. Internal Revenue Code Section 165(d) prohibits gambling losses in excess of wins. Every state with a state income tax conforms to this.
But state conformity to the TCJA is decidedly mixed. California does not conform to almost any part of the TCJA. The Franchise Tax Board produced a publication showing each change in law and the impact to California. At the bottom of page 89 is the beginning of the discussion on Section 11050 of the TCJA (which changed the rules for professional gamblers). The FTB publication notes:
California conforms, under the PITL, to the federal rules relating to the deduction for losses from wagering transaction[s] under IRC section 165(d), as of the specified date of January 1, 2015, but does not conform to the federal limitation on the deduction.
Thus, a California professional gambler can take a loss based on his business expenses on his state tax return.
Massachusetts also doesn’t conform to federal law in this area. However, Massachusetts does not allow losses from any business to be reported on its tax returns. Thus, a Massachusetts professional gambler wasn’t able to take a loss based on his business expenses in the past and cannot today.
State conformity on the provisions of the TCJA will vary among the states. If you reside in or must pay state taxes, this is a key issue that you must discuss with your tax professional.