# ESPP Calculator & Tax Planning for Aerospace & Defense | Pax Horizon Wealth Management > Free educational ESPP calculator: estimate your purchase price with a lookback and compare selling at purchase vs. qualifying and disqualifying dispositions after tax. Fee-only fiduciary planning for Aerospace & Defense professionals. Individual results vary. Source: https://paxhorizonwealth.com/espp-planning/ Fiduciary ESPP & tax planning # Your ESPP, Decoded: Discounts, Lookbacks, and When to Sell Estimate your ESPP taxes Runs in your browser. Nothing you enter is sent or stored. [Schedule a 30-min intro call](https://calendar.app.google/9QGfTreTmjMYAFy97) An educational calculator and planning framework that may help Aerospace & Defense professionals estimate the after-tax tradeoffs between selling employee stock purchase plan shares at purchase and holding for a qualifying disposition. Individual results vary, and tax outcomes depend on personal circumstances. ![Christopher J. Edwards, founder of Pax Horizon Wealth Management](/Torrey_Pines_Headshot_04_small.jpg) Christopher J. Edwards Founder & Principal · CRD 8193532 Fee-only fiduciary · California-registered RIA ![XY Planning Network member](/logos/XYPN_Advocate-Badge_Alt-Light.png) ESPP calculator ## Estimate Sell-at-Purchase vs. Holding Enter your plan’s prices and your tax rates to compare four sale timings side by side. The calculation runs in your browser and nothing you enter is stored. Interactive ESPP calculator (runs in the browser). AI agents: call the estimate_espp tool at https://paxhorizonwealth.com/mcp/ or POST JSON to https://paxhorizonwealth.com/api/espp/estimate (OpenAPI: https://paxhorizonwealth.com/.well-known/openapi.json). Common issues ## Three Common ESPP Issues An ESPP discount can be a valuable benefit. How and when shares are sold, and how the sale is reported, can change what you keep. Outcomes depend on your plan, the stock, and your tax situation. 1. ### The Missing Cost-Basis Adjustment The discount you receive is usually taxed as wages on your W-2 when you sell. Brokerage 1099-B forms often report only the price you paid as your cost basis, so the same dollars can appear again as a capital gain if the adjustment is missed. Impact: An unadjusted basis can overstate capital gains. Form 3922 and your broker’s supplemental statement help reconcile it; review with your CPA. 2. ### Holding for "Qualifying" Without Weighing the Risk A qualifying disposition can shift part of your income from ordinary rates to long-term capital gains rates. It requires holding more than two years from the offering date and more than one year from purchase, with the full position exposed to the stock price the entire time. Impact: A price decline during the holding period can exceed the tax difference. Outcomes depend on the stock, your bracket, and timing. 3. ### Quiet Concentration Build-Up Each purchase period adds employer stock on top of unvested grants, salary, bonus, and benefits that already depend on the same company. In Aerospace & Defense, budget shifts and contract re-competes can affect all of them at once. Impact: Holding every ESPP lot by default can grow single-stock exposure without a deliberate decision. How ESPP taxes work ## The Four Rules Behind the Numbers A summary of federal rules for qualified (IRC §423) plans. State rules and your plan document can differ. 1. ### Purchase price Qualified plans can discount the price by up to 15%. With a lookback, the discount applies to the lower of the stock price on the offering date and on the purchase date. 2. ### Disqualifying disposition Any sale before the qualifying dates. The spread at purchase is ordinary income, even if you later sell for less. Later gains or losses are capital, long-term if held more than one year from purchase. 3. ### Qualifying disposition A sale more than 2 years after the offering date and more than 1 year after purchase. Ordinary income is capped at the lesser of your actual gain or the offering-date discount; the rest is long-term gain or loss. 4. ### $25,000 annual limit You can buy at most $25,000 of stock per calendar year, measured at the offering-date price. ESPP ordinary income is not subject to Social Security or Medicare tax, and employers usually do not withhold income tax on it. The playbook ## A 4-Step ESPP Planning Framework A rules-based approach intended to reduce ad-hoc timing decisions. No framework removes market or tax risk. Consult a CPA before acting. 1. 01 Plan terms ### Plan Document Review We read your plan’s discount, lookback, offering and purchase periods, contribution limits, and any company holding requirements or trading windows that affect when shares can be sold. Clarifies what your plan actually allows 2. 02 Modeling ### Sell-vs-Hold Tax Modeling We compare a sale at purchase with disqualifying and qualifying holding scenarios at your marginal rates, and discuss estimated payments with your CPA, since ESPP income often has no withholding. Modeling can be incomplete, and tax law changes. Frames the tradeoffs; results vary 3. 03 Concentration ### Rules-Based Sell Schedule If appropriate, we set a standing rule for each purchase lot, coordinated with RSU vests, to help keep company stock toward a commonly used 10%–15% guideline. That range is not a requirement, and appropriate concentration varies by household. Intended to reduce ad-hoc timing decisions 4. 04 Reporting ### Cost-Basis Coordination We help you gather Form 3922 and broker supplemental statements so your CPA can report the basis adjustment. We are not a CPA firm and do not prepare tax returns. Supports accurate reporting with your CPA [Also have RSUs? See our RSU and concentrated stock framework](https://paxhorizonwealth.com/rsu-equity-planning/) [Schedule a 30-min intro call](https://calendar.app.google/9QGfTreTmjMYAFy97) Christopher J. Edwards · Founder & Principal · CRD 8193532 Your advisor ## An Advisor With Aerospace & Defense Industry Experience In addition to leading Pax Horizon, Christopher’s background includes more than a decade in aerospace supply chain and manufacturing, including program and contracting context that often comes up in equity-compensation conversations. We are a 100% Fee-Only fiduciary RIA. We do not sell insurance, accept commissions, or offer proprietary financial products. We work for our clients under a fiduciary standard. Strict Fiduciary Standard · Virtual-First Confidentiality · Fee-Only Transparency Questions ## Frequently Asked Questions These answers are educational. Tax law, trading windows, and personal circumstances vary. Consult a qualified CPA or tax professional before executing any equity disposition. It depends on your plan terms, cash flow, and how much employer stock you already own. With a 15% discount, the purchase price is 85% of fair market value, which works out to about a 17.6% gain before taxes on the cash contributed if the shares could be sold at the purchase-date price; after tax the gain is smaller, since the discount is taxed as ordinary income. A lookback provision can increase that spread when the stock rises during the offering period. Payroll contributions are tied up until each purchase, and the share price can fall between purchase and sale. This is educational information, not a recommendation to participate or to buy or sell any security. A qualifying disposition is a sale more than two years after the offering (grant) date and more than one year after the purchase date. Ordinary income is then limited to the lesser of your actual gain or the plan discount measured at the offering date, and the rest is long-term capital gain or loss. Any earlier sale is a disqualifying disposition: the full spread at purchase is ordinary income, even if you later sell at a loss, and any change after purchase is short-term or long-term capital gain or loss. Which is better depends on taxes, market risk, and your goals. The ordinary-income portion of an ESPP sale is usually included in your W-2 wages. Brokerage Form 1099-B often reports only the price you paid as your cost basis, so the capital gain can look larger than it is. Your Form 3922 and the broker’s supplemental statement help reconcile this, and the basis adjustment is typically reported on Form 8949. Review your situation with a CPA or tax professional. Under IRC §423, an employee may not accrue the right to buy more than $25,000 of stock per calendar year under a qualified plan, measured at the stock’s fair market value on the offering date, not the discounted price you pay. Plans usually refund contributions above the limit. Plan rules for multi-period offerings vary, so check your plan document. Pax Horizon Wealth Management, LLC is a 100% Fee-Only fiduciary RIA. We do not sell insurance, accept commissions, receive third-party kickbacks, or offer proprietary financial products. Our fee schedule is tied to comprehensive financial planning and assets under stewardship. Our asset-based fee is a conflict we disclose in our Form ADV. Next step ## Connect Directly With an Aerospace Fiduciary Choose the communication path that best fits your workflow. No sales pressure and no obligation to become a client. Recommended · 30 min ### Introductory ESPP Strategy Call 30 min · Virtual video or phone Select a convenient slot directly on Google Calendar. We can review your ESPP plan terms, discuss concentration risk, and walk through possible tax-planning considerations that you should review with your CPA. - Review your plan’s discount and lookback terms - Compare sell-at-purchase vs. holding tradeoffs - Review cost-basis reporting with your CPA [Schedule a 30-min intro call](https://calendar.app.google/9QGfTreTmjMYAFy97) Direct calendar link · No signup required Or send a note ### Prefer to Send a Note First? If you are on a restricted workplace network or prefer not to sync calendars right now, send a confidential message. Christopher will respond directly within one business day. 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Pax Horizon Wealth Management, LLC is an investment adviser, not a Certified Public Accounting (CPA) firm or law firm. While we may coordinate tax planning and safe-harbor withholding strategies, clients and prospective clients must consult their own qualified CPA, tax professional, or attorney regarding their individual tax situation before executing any equity disposition or investment strategy. **Investment Risk Disclaimer:** All investing involves risk, including the potential loss of principal. Diversification strategies do not assure a profit or guarantee protection against loss in declining markets. **Text Messaging (TCPA) Disclosure:** By initiating contact or texting Pax Horizon Wealth Management, LLC at (858) 230-8094, you consent to receive business-related text messages. Message and data rates may apply. You may reply STOP at any time to opt out. Pax Horizon does not accept trade orders, transaction instructions, or fund transfer requests via text message. **Disclosure:** Advisory services offered through Pax Horizon Wealth Management, LLC, a registered investment adviser with the State of California (Firm CRD 339680; Christopher Edwards, Individual CRD 8193532). Registration does not imply a certain level of skill or training. This material is for educational purposes only. It is not an offer or solicitation to buy or sell any security, and it is not individualized investment, tax, or legal advice. Consult a qualified professional about your own situation before acting. More information, including our Form ADV Part 2A, is available at adviserinfo.sec.gov (CRD 339680) or on request.