Typical comp shape
Frontend engineers usually earn rsu, isos at pre-ipo. Common employers include Vercel, Shopify, Airbnb, Figma. Frontend hires at design-forward pre-IPO companies often receive ISOs where AMT exposure drives the exercise timing question.
What Missouri changes
In Missouri, every RSU vest, NSO exercise, and ESPP purchase carries 4.8% state tax on top of federal. For a senior frontend engineer with $300k+ of equity income, the state layer routinely adds $25-45k to the annual bill.
Planning cadence
For a frontend engineer in Missouri, the three planning windows are: after each RSU vest (withholding check and sell-vs-hold), before any ISO exercise (AMT model at federal only), and in Q4 (estimated tax top-up to clear the safe harbor).