California Bonus Tax Calculator 2026

Two flat rates, and bonuses get the higher one

EDD's California Employer's Guide (DE 44, 2026) splits supplemental wages into two groups. Bonuses and stock options are withheld at 10.23%; overtime, commissions, sales awards, severance and vacation pay at 6.6%. Both rates ignore the allowances on your DE 4. On a $5,000 bonus, California income tax withholding is $511.50.

The flat rates are only available when the bonus is not paid together with regular wages. If it arrives in the same check, EDD requires the employer to treat the total as regular wages and use the withholding schedules. When it is paid separately, the employer may still choose the aggregate approach instead of 10.23%.

SDI has no ceiling

State Disability Insurance, which funds both disability and Paid Family Leave benefits, is withheld at 1.3% in 2026. Since January 1, 2024 there is no SDI taxable wage limit, so every dollar of a bonus pays it — $65.00 on $5,000, and $650.00 on a $50,000 bonus. Before 2024, high earners stopped paying SDI partway through the year; that no longer happens.

Lowering the California bite

A 401(k) deferral reduces California withholding as well as federal: deferring 10% of the $5,000 bonus lowers the California line to $460.35 and leaves a check of $2,602.15 plus $500 in the plan. SDI is still owed on the deferred amount. California's 10.23% is a withholding rate; your actual California tax on the bonus is set by your bracket when you file.