Most ISO planning conversations focus on minimizing the AMT hit. But there's a year-specific opportunity that often gets overlooked: a high W-2 year may be one of the best times to exercise.
Here's the logic.
AMT is only triggered when your AMT liability exceeds your regular tax. In a year where income is already elevated—large bonus, heavy RSU vests, equity event—regular tax climbs significantly. That gap between regular tax and AMT is your exercise window. It's called AMT cover, and it represents the amount of ISO spread you can absorb without owing a dollar of AMT.
The higher your regular tax, the more spread you can take on without crossing into AMT territory. A strong W-2 year effectively subsidizes your ISO exercise.
To find your ceiling, you need to model both tax calculations side by side—your projected regular tax versus your projected AMT—and identify the spread amount that keeps you just below the crossover. That number is actionable. It tells you exactly how many shares you can exercise, at what spread, before AMT kicks in.
The timing window matters: this modeling needs to happen before December 31. Once the year closes, so does the opportunity.
If this year is tracking toward a compensation spike—bonus, accelerated vests, or a liquidity event—it's worth running the numbers to see how much ISO exercise the year can absorb before AMT becomes a factor.
This post is for educational purposes only and is not intended as tax or financial advice. Please consult a qualified tax advisor regarding your specific situation.