SpaceX IPO'd three weeks ago. The lockup clock is running — and so is the tax clock.

What happened (as reported)

Your lockup calendar: specific dates

SpaceX's reported lockup is staggered across multiple windows, not a single 180-day gate. Based on the June 12, 2026 IPO date, here is the reported schedule in calendar terms. Eligible percentages and specific dates depend on your holder class and grant terms — confirm with your equity portal and company communications.

The staggered structure is a gift to planners and a trap for procrastinators: you have defined windows in 2026 — but each is brief. Deciding in the window is how people freeze. Map your tranche calendar now and pre-commit what sells in each.

The settlement tax event: what you owe and what was withheld

RSU settlement on June 12 created a taxable event. Here's the mechanics:

• Settlement income is ordinary income under IRC § 83.¹ Each settled RSU was valued at the SPCX price on June 12 and included in your 2026 W-2. A meaningful RSU grant at IPO-day prices can represent a year or more of salary as a single taxable event — taxed at your top marginal rate, potentially 35–37% federal plus state.
• Withholding was at 22% — your real rate may be 35–37%. The IRS requires employers to withhold at the supplemental rate — 22% federal for income under $1 million.² That 13–15 point gap on a large settlement is an April 2027 liability right now. Use the RSU settlement tax estimator to size your federal gap.
• New vests keep settling. Ongoing RSU vests after the IPO create the same withholding-gap dynamic each cycle. Quarterly estimated payments stay relevant as long as vesting is a material income source.

The Q3 estimated tax deadline is September 15

The Q2 estimated tax deadline was June 16 — four days after the IPO. Most employees who settled RSUs on June 12 didn't have time to calculate a voluntary Q2 payment. The employer withholding that happened at settlement counts toward your 2026 tax liability, but if it undershoots your real rate, the gap compounds into an underpayment penalty unless you close it through later payments.

• Q3 deadline: September 15, 2026. The IRS safe harbor to avoid underpayment penalties: pay at least 110% of your prior-year tax liability (if your 2025 AGI exceeded $150,000), or at least 90% of your 2026 liability, by year-end.³ If 2025 was a normal income year, the 110% safe harbor may be the more achievable target.
• Q4 deadline: January 15, 2027. Final quarterly window for 2026. The penalty for underpayment is annualized and is typically worth addressing — particularly when the underpayment came from a large one-time event like an IPO settlement.
• California follows its own schedule. CA FTB quarterly deadlines are April 15, June 16, September 15, and January 15. If you're a California resident, estimated payments are made to both the IRS and FTB. The CA underpayment interest rate has historically exceeded the federal rate.

California employees vs Texas employees: the state tax gap

SpaceX has two major employee populations with very different state-tax situations:

• California (Hawthorne headquarters). California taxes ordinary income — including RSU settlement — at rates up to 13.3% (12.3% above roughly $625,000 for single filers; 13.3% above $1 million).⁴ California also taxes capital gains as ordinary income — there is no preferential LTCG rate at the state level. This is the highest state income-tax environment for SPCX equity: combined federal + state ordinary income can exceed 50% for high earners.
• Texas (Boca Chica / Starbase and other TX locations). Texas has no state income tax. RSU settlement, option exercise spread, and capital gains are federal-only for true Texas residents. If you relocated from California to Texas, California may still claim tax on income attributable to California-service periods under its source-income rules — document the move and work-location history carefully.
• Multi-state employees. If your grant years spanned employment in multiple states, each state may claim a prorated share of settlement income under source-income rules. This is particularly common for employees who joined from elsewhere or relocated between Hawthorne and Starbase. Sorting out multi-state allocation requires your complete grant-period work-location history.

Options: now that you have a public reference price

SPCX employees with ISOs or NQSOs now have a real public-market price to model against. Exercise decisions change significantly now that there's no 409A complexity and prices update in real time:

• ISOs and the AMT spread. Exercising ISOs triggers AMT preference income equal to the spread (FMV minus strike). With a public market price, you can calculate the exact AMT exposure before exercising. Use the ISO exercise and AMT calculator to size the AMT bill and compare it against the potential LTCG benefit from holding the exercised shares for 1+ year. The 2026 AMT exemption is $90,100 single / $140,200 MFJ per OBBBA (phaseout at 50 cents per dollar above $613,150 / $1,226,300).
• NQSOs and ordinary income at exercise. NQSO exercise locks in the spread as ordinary income in the year of exercise, subject to FICA (SS wage base $184,500 for 2026; Medicare 1.45% plus 0.9% over $200K single / $250K MFJ) and federal plus state income tax at your top rate. Exercise-and-sell is taxed entirely at ordinary income rates; exercise-and-hold starts a LTCG clock. See the NQSO tax guide for the full mechanics.
• QSBS and Section 1202. SpaceX was incorporated in 2002 and has long since exceeded the $75 million gross-asset threshold for QSBS eligibility under IRC § 1202.⁵ Most current SPCX equity will not qualify. If you held stock or options from SpaceX's very early years when the company was below the threshold, a tax attorney can review whether any specific shares may qualify.

10b5-1 plans for SPCX employees: timing right now

If you're an officer, director, or in a role with regular access to material nonpublic information, you need a structured plan to sell in the lockup windows. Under SEC Rule 10b5-1, as amended effective February 27, 2023 (Release 33-11138):⁶

• Non-officers: 30-day cooling-off period. If you adopt a plan today (July 3, 2026), you're eligible to execute trades starting around August 2, 2026 — before the Day 70 tranche (August 21) opens. Non-officer SPCX employees who want systematic selling in the August–December windows should consider adopting a plan now during any open trading window.
• Officers and directors: 90-day cooling-off (or next earnings + 2 days, if later). SpaceX's Q2 earnings release (expected late July to early August) plus two business days — call it approximately mid-August — versus 90 days from today (October 1). The later date controls, making October 1, 2026 the earliest eligible trading date for an officer who adopts today. This aligns with the Day 120 (October 10) and Q3-earnings-unlock tranches.
• One plan at a time for officers. The 2023 amendments prohibit officers from maintaining multiple concurrent single-trade arrangements. Plan once; execute through it.

See the 10b5-1 trading plans guide for the full SEC mechanics, worked SPCX timelines, and step-by-step adoption process.

Six planning steps for SPCX employees this summer

1. Pull your lot report. Log into your brokerage or equity portal and list every SPCX lot — settlement date, cost basis (the June 12 IPO-day settlement price), and current unrealized gain or loss. For option holders, list each grant with strike price, shares, vesting status, and type (ISO vs NQSO).
2. Size the withholding gap and plan for Q3. The RSU settlement at IPO-day prices was withheld at 22% federal. If your marginal rate is 35–37%, the gap is 13–15 points on the full settlement amount. Use the RSU estimator and consider making a Q3 estimated payment by September 15 to reduce April 2027 concentration.
3. Set your concentration target before the first unlock window. Pick a number: what percentage of net worth should remain in SPCX after each window? That target drives all sell decisions. Make this decision while you can think calmly — before Q2 earnings unlock opens and urgency distorts the math. The concentration calculator models the multi-year glidepath.
4. Map your tranche calendar. For each unlock window: (a) what's the maximum you can sell, (b) what's your target, (c) how much do you plan to sell, and (d) what's the tax cost? Pre-commit the tranches in a spreadsheet before the window opens.
5. Consider a 10b5-1 plan if you have insider exposure. If you're in a role with MNPI access, talk to legal counsel during a current open window. Non-officers can adopt now and start selling in August; officers can adopt now and start selling in October. Don't wait until a blackout period limits your options.
6. Model option exercises with real prices. If you hold ISOs or NQSOs, model the exercise cost, AMT exposure (for ISOs), and holding-period strategy against the live SPCX market price. The ISO/AMT calculator and NQSO guide provide the framework; a fee-only advisor can run the scenario for your specific income and state.

Just want to buy SPCX?

SPCX is a public stock — any brokerage works. This page is for employees and early holders managing RSU settlement, lockup windows, option decisions, and concentrated equity from years inside SpaceX. For pre-IPO planning at other companies currently pre-IPO, see OpenAI or Anthropic. For what the lockup period looks like end-to-end, see the IPO lockup playbook.

The first unlock window is weeks away. Plan it now.

Get matched with a fee-only fiduciary who works with post-IPO equity — SPCX lockup calendars, settlement tax modeling, 10b5-1 plan design, and California vs Texas state-tax planning. Free, no obligation.