Who's fiscal year does he want to use? If claiming it on last year is a big problem I'd say put it on 2000 and if the IRS questions it, make sure to explain it as 2000 income. Alternate plan "B" if it doesn't hurt him, just claim it on 1999. Either way, he should be able to take advantage of the casinos accounting methods and apply the income to whatever year he feels is best for his situation.