California severance is generally reportable as income, but the amount withheld from the payment is not the same as the final tax calculated on an annual return. For a separately identified payment, an employer may use California's published 6.6% supplemental-wage withholding rate for severance. Payroll may use an aggregate method instead, so 6.6% is not a promise of what every pay statement will show.
The same distinction applies federally. The IRS permits an optional 22% federal income-tax withholding method on qualifying separately identified supplemental wages below the $1 million cumulative threshold. An employer may instead combine the payment with regular wages and use the payroll tables. The portion of cumulative supplemental wages from the same employer above $1 million is subject to mandatory 37% federal withholding.
The Short Answer: Withholding Is Not Final Tax
Three different calculations are easy to mix together:
- Payment-time income-tax withholding. Payroll sends an estimated prepayment to the federal and state tax authorities.
- Payroll taxes. Social Security, Medicare, and, where applicable, California State Disability Insurance (SDI) are separate lines.
- Final annual tax liability. Filing status, total annual income, deductions, credits, and other income determine the tax calculated on the return. It may be higher or lower than the amount withheld.
That is why adding 22% and California's top marginal income-tax bracket does not produce a reliable severance “tax rate.” It combines a withholding method with a possible annual marginal rate and leaves out the conditions that determine both.
2026 California Severance Withholding Components
| Component | 2026 payment-time treatment | Important condition | |---|---|---| | Federal income-tax withholding | Optional 22% flat method | Available for qualifying separately identified supplemental wages when the IRS conditions are met; payroll may aggregate instead. The excess over $1 million in cumulative supplemental wages from the employer is withheld at 37%. | | California PIT withholding | Optional 6.6% supplemental rate for severance | Applies to separately paid “other supplemental wages”; payroll may use the aggregate method instead. | | Social Security | 6.2% | Applies only until the employee reaches the 2026 Social Security wage base of $184,500 with that employer. | | Medicare | 1.45% | No wage cap. An employer also withholds 0.9% Additional Medicare Tax after Medicare wages from that employer exceed $200,000. | | California SDI | 1.3% | California lists dismissal or severance pay as subject to SDI unless specified statutory conditions apply. There is no SDI taxable-wage cap in 2026. |
Official references: the 2026 California Employer's Guide describes the 6.6% supplemental rate and aggregate method; EDD's Types of Payments information sheet describes the treatment of dismissal or severance pay; EDD publishes the 2026 SDI rate; and IRS Publication 15 describes federal supplemental-wage and payroll-tax rules.
Worked Payment-Time Example: $50,000
Assume all of the following solely for this illustration:
- the employer separately identifies a $50,000 severance payment;
- payroll uses the optional 22% federal method and California's 6.6% supplemental method;
- the employee has no prior 2026 Social Security or Medicare wages from this employer;
- the payment is subject to California SDI; and
- no local tax, benefit deduction, or other adjustment applies.
| Line | Illustrative estimate | |---|---:| | Gross severance | $50,000 | | Federal income-tax withholding (22%) | -$11,000 | | California PIT withholding (6.6%) | -$3,300 | | Social Security (6.2%) | -$3,100 | | Medicare (1.45%) | -$725 | | California SDI (1.3%) | -$650 | | Total estimated withholding and payroll deductions | -$18,775 | | Estimated payment after these lines | $31,225 |
These are illustrative estimates, a starting point rather than a final figure. Actual withholding may be higher or lower. The example does not calculate final federal or California income-tax liability, and it changes materially when year-to-date wages have already used part or all of the Social Security wage base.
Use the severance tax calculator to add the payment amount, state, and year-to-date wage figures. It models federal income-tax, federal payroll-tax, and state income-tax lines, but it does not add California SDI. Its result remains a withholding estimate, not a tax return.
Why Payroll May Not Use 6.6%
California's 6.6% figure is a published supplemental-wage withholding option for separately paid severance. It is not California's final annual income-tax rate and it is not the only permitted payroll method.
If the severance is combined with regular wages, or payroll chooses the aggregate method, the employer calculates withholding using California's wage-bracket or exact-calculation schedules. The resulting percentage can be above or below 6.6%, depending on the pay-period calculation and information on file.
The same method choice exists below the federal $1 million threshold. A pay statement showing something other than exactly 22% federal or 6.6% California does not, by itself, establish an error. Payroll can identify the method used and the year-to-date wage figures included.
Social Security, Medicare, and SDI
Federal severance pay is treated as supplemental wages and is generally subject to Social Security and Medicare taxes. For 2026:
- Social Security is 6.2% up to the $184,500 wage base. If wages from the same employer have already reached that base, additional severance from that employer should not add Social Security tax.
- Medicare is 1.45% without a wage cap.
- Employers begin withholding an additional 0.9% Medicare tax after Medicare wages they pay to an employee exceed $200,000. Final Additional Medicare Tax liability can differ because the return uses the applicable filing-status threshold.
EDD publishes a 1.3% SDI rate for 2026 and no taxable-wage cap. Its payment-classification sheet lists dismissal or severance pay as subject to SDI unless the conditions referenced there are met. Payroll or EDD can confirm how a specific payment is classified.
Higher-Income California Returns
California's final liability is calculated on the annual return, not by applying 6.6% to every severance dollar. The state also imposes a 1% Behavioral Health Services Tax on taxable income above $1 million. The tax applies only to the portion above that threshold and belongs to the return calculation, not the basic 6.6% payment-time example. The 2026 Form 540-ES instructions describe that threshold.
Questions Payroll or a Tax Professional Can Clarify
Useful questions include:
- Will the payment be identified separately from regular wages?
- Which federal and California withholding methods will payroll use?
- How much 2026 Social Security, Medicare, and supplemental wages has this employer already paid?
- Will California SDI apply to this payment classification?
- Are city, benefit, retirement-plan, or other deductions included?
- How could the payment timing interact with total annual income and estimated-tax requirements?
Payroll can explain the employer's calculation. A qualified tax professional can assess final tax liability and payment timing using the complete return. Questions about release terms, payment obligations, or legal rights belong with a licensed California employment attorney.
California Withholding Compared With No-Income-Tax States
Texas and Florida do not levy state individual income tax on wages. California does. That creates a payment-time difference, but a simple state comparison cannot determine final liability or whether California-source rules apply to a particular payment.
For a separately paid $50,000 example using the optional methods, California PIT withholding would be $3,300 while Texas and Florida state income-tax withholding would be $0. Federal and payroll-tax lines still apply. Residency, work location, sourcing, and payment terms can change the analysis, so a move before payment should not be treated as an automatic tax result.
See the California severance information page for the broader employment context, or use the main severance calculator for an estimated gross package range. Neither tool calculates final tax or determines legal rights.