Apple RSU Taxes in California (2026)

2026 Apple Compensation Benchmarks in California

Below is the 2026 tax withholding and April shortfall breakdown across sample Apple engineering levels for a Single filer in California (at a reference share price of $235/share via E*TRADE by Morgan Stanley):

California Supplemental Tax Regulations for Apple RSUs

California Franchise Tax Board (FTB) mandates a 10.23% flat supplemental wage withholding rate for stock options and RSU vests under Cal. Rev. & Tax. Code § 18663. However, California enforces a steeply progressive bracket system reaching 11.3% above $418,961, 12.3% above $698,271, and 13.3% above $1,000,000 (via the 1% Mental Health Services Tax), plus an uncapped 1.1% California State Disability Insurance (CASDI) payroll tax on all W-2 wages and RSU vests.

California Bracket Architecture: 9 progressive brackets from 1.0% to 12.3%, plus a 1.0% Mental Health Services surtax over $1,000,000 (13.3% top income rate) and 1.1% uncapped SDI payroll tax.

California Safe Harbor & Estimated Tax Vouchers (FTB Form 540-ES (Estimated Tax for Individuals))

California Form 540-ES follows an uneven 30% (Q1), 40% (Q2), 0% (Q3), and 30% (Q4) payment schedule. Critically, once California AGI reaches $1,000,000, the prior-year safe harbor (110%) is completely revoked—forcing taxpayers to remit at least 90% of current-year California tax liability.

Multi-State Relocation & Nonresident Sourcing Rules in California

Under the California FTB Equity-Based Compensation Guidelines (FTB Pub. 1004), if you work in California for part of the RSU vesting period and relocate to a zero-tax state (such as WA or TX) before the vest date, California still taxes the fraction of the RSU vest corresponding to California workdays divided by total workdays from grant date to vest date.

Employer Stock Plan Specifics: Apple (E*TRADE by Morgan Stanley)

Unlike companies that vest monthly or quarterly, Apple’s standard RSU grants vest semi-annually—most commonly on April 15 and October 15. Concentrating a full year of equity compensation into just two vest dates creates two massive liquidity and tax events per year. Furthermore, the April 15 vest lands on the exact same day that both prior-year April tax balances AND Q1 1040-ES estimated taxes are due.

Withholding Election Guidance: Log in to E*TRADE Stock Plan (or Apple’s internal people portal) at least 2–3 weeks before April 15 or October 15 to verify whether supplemental tax withholding rate elections are open for your grant type. In addition, Apple employees participating in the Employee Stock Purchase Plan (ESPP) with a 15% lookback discount should account for disqualifying disposition ordinary income on their W-2.

2026 Statutory Parameters Quick Reference