Plan your Castelion NSO exercise
Calculator · free · no signup · pre-IPOCastelion is pre-IPO. Plan your NSO exercise tax (federal, state, FICA) at any expected valuation.
Beta · invite-only · AlphaLatitude Inc. · Free Tools
Your grant
Seeded from secondary-market data, as of Jun 6, 2026
Tax inputs
Hold strategy
Best after-tax payout — at year 1
$377,460
Sell + invest wins by $193,847 over Hold 1 yr.
Estimates only. Not financial advice.
Sell + invest
Best payout| Bargain element (sale − strike) | $686,450 |
| Federal | |
| State | |
| Medicare | −$9,954 |
| Additional Medicare | −$6,178 |
| Market gain over 1 yr at 10.0% | $35,214 |
| LTCG on diversified gain (fed + state + NIIT) | −$9,895 |
| Net at year 1 | $377,460 |
Sell every share immediately; invest the after-tax cash at the market return for 1 yr, then liquidate. Diversified — no single-stock concentration risk.
Exercise + hold 1 yr
| Sale proceeds (year 1) | |
| LTCG tax (federal + state + NIIT) | $0 |
| Net at year 1 | $183,614 |
Sold 2,609 shares at exercise to cover strike + tax; 2,391 shares held 1 yr for LTCG.
Social Security + Medicare are payroll taxes (collectively called FICA) — they apply because you're exercising as a current employee.
Both columns are stated in year-1 dollars: sell-now proceeds compound at the market return and pay LTCG on the gain at year 1; any cash paid out of pocket on the hold side carries the same opportunity cost.
Net at year N — by hold period
Estimates only. Excludes AMT (NSOs do not trigger AMT), state-AMT, multi-state moves, and disqualifying-disposition edge cases. Not financial advice.
You calculated one NSO decision. The beta plans NSOs alongside RSUs and ISOs in a single multi-year tax plan.
Request beta access →About Castelion
Castelion is a privately held Aerospace/Defense company, incorporated in Delaware and headquartered in Torrance, CA.
Last reported secondary-market price: $147.29 per share (as of 2026-06-06). Your own 409A may differ.
Hypersonics.
Equity grants at Castelion typically include incentive stock options (ISOs) and non-qualified stock options (NSOs).
Castelion, founded in November 2022 in El Segundo, California by SpaceX alumni Bryon Hargis (CEO), Sean Pitt (COO), and Andrew Kreitz (CFO), builds hypersonic weapons for the Pentagon at production scale. In 2.5 years the team advanced a clean-sheet hypersonic design through more than 25 flight tests. The company raised $100 million in a Series A in January 2025 and $350 million in a Series B in mid-2025, with Altimeter Capital and Lightspeed Venture Partners co-leading alongside Andreessen Horowitz and General Catalyst. Total disclosed funding exceeds $460 million.
Sources: castelion.com · techcrunch.com
OptionsAhoy is an independent tool and is not affiliated with, endorsed by, or sponsored by Castelion.
Castelion NSO exercise creates ordinary income on the bargain element (federal, state, and FICA) at the price on the day you exercise. The calculator works at any valuation, so you can model your exercise cost at the current 409A FMV, an expected IPO price, or post-IPO scenarios.
Example: at Castelion's last reported price of $147.29, exercising 5,000 NSOs with a $44.19 strike creates a $515,500 bargain element, taxed as ordinary income on the day you exercise. Combined federal + state + FICA on that bargain typically lands between $139,185 and $231,975 depending on your bracket and state. The calculator above computes the exact figure for your situation and compares selling now vs. holding through the long-term capital-gains threshold.
All Castelion tools → · Use the generic NSO Exercise Calculator for any company.
Castelion equity questions
- How is a Castelion NSO exercise taxed?
- Exercising a non-qualified stock option (NSO) creates ordinary income on the bargain element (the price on the day you exercise minus your strike), subject to federal income tax, state income tax, and FICA. The calculator above computes that tax for your Castelion grant and compares selling the shares now against holding past the one-year mark for long-term capital-gains treatment.
- Does Castelion grant ISOs, NSOs, or RSUs?
- Equity compensation at Castelion typically takes the form of incentive stock options (ISOs) and non-qualified stock options (NSOs). Incentive stock options can trigger the alternative minimum tax (AMT) when you exercise.
- Are Castelion shares eligible for QSBS?
- They might be. Qualified small business stock (QSBS) under Internal Revenue Code Section 1202 can exclude federal tax on much of the gain when shares were acquired at original issuance from a C-corporation while its gross assets were under $50 million, and held at least five years. Whether your Castelion shares qualify turns on when you acquired them and the company's asset size at that time.
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OptionsAhoy plans your Castelion equity alongside hedging, vesting, and de-concentration, across bullish, neutral, and bearish market scenarios. Free during beta.