How are bonus bets taxed?

There is no IRS guidance written for sportsbook bonus bets. Ask your CPA how to treat them.

How TaxVig will count them

A win counts what the book credited. A loss counts as zero, since none of your own money was at risk.

Example: a $50 bonus bet at +200 pays $100, so we count $100, not $150.

All gambling winnings are reportable (IRS Topic 419). Deposit bonuses and site credit are a separate question for your CPA.

A calculator, not tax advice. Show this to your CPA. Run your own totals.