KLA vesting in Massachusetts
KLA runs a quarterly RSU vesting schedule. For Massachusetts residents, each vest is a taxable event: federal supplemental withholding at 22% up to $1M YTD and 37% above, plus 9% state withholding at the top Massachusetts bracket, plus Medicare, plus Social Security up to the annual wage base.
The withholding gap
A senior KLA engineer earning $300k base plus $400k RSU in Massachusetts sits at a combined marginal rate near 44.0%. Federal supplemental withholds only 22% on the RSU portion. The gap shows up at April filing unless you cover it with quarterly estimates or W-4 additional withholding.
Massachusetts-specific planning moves
Massachusetts taxes long-term capital gains as ordinary income, so holding past one year gives only federal savings (LTCG 15-20% versus ordinary 32-37%). State 9% applies either way.
Moving in or out
If you plan to move during an active $KLA vesting schedule, trailing-nexus rules apply. Massachusetts will generally source the portion of each tranche earned while you were a resident, via workday allocation between grant and vest. Document your move date, work location per pay period, and any remote-work arrangements.