Advanced Tax Concepts and Special Rules
Learn about advanced tax concepts that affect equity compensation planning, including AMT credits, wash sale rules, capital loss limitations, and special considerations.
Alternative Minimum Tax (AMT) Credits
What Are AMT Credits?
When you pay AMT in one year (often due to ISO exercises), you may generate AMT credits that can be used in future years to reduce your regular tax liability.
How AMT Credits Work
- Generate Credits: Pay AMT in Year 1 (e.g., from ISO exercise)
- Carry Forward: Credits carry forward indefinitely to future years
- Use Credits: In years when regular tax exceeds AMT, credits reduce your regular tax
- Limitation: Credits can only reduce regular tax down to the AMT amount
Why This Matters for ISO Planning
ISO exercises create a timing difference—you pay AMT now but may recover those taxes through credits later. This makes ISO exercises less costly than they initially appear, but requires multi-year tax planning.
Example:
- Year 1: Exercise ISOs, pay $20,000 in AMT (generate $20,000 credit)
- Year 2: Regular tax is $50,000, AMT is $25,000
- Credit reduces regular tax: $50,000 - $20,000 = $30,000 (still above AMT floor of $25,000)
- Net benefit: Recovered the $20,000 paid in Year 1
Wash Sale Rules
What Is a Wash Sale?
A wash sale occurs when you sell a security at a loss and purchase substantially identical securities within 30 days before or after the sale (61-day window total).
The Wash Sale Rule
You cannot claim the capital loss for tax purposes. Instead, the disallowed loss is added to the cost basis of the replacement shares.
How It Affects Equity Compensation
Common Scenario:
- Client sells company stock at a loss
- Client receives RSUs that vest within 30 days
- Wash sale rule is triggered
- Capital loss is disallowed
Planning Consideration:
- Be aware of vesting schedules when selling stock at a loss
- Consider timing sales outside the 61-day window of vesting events
- Disallowed losses aren't permanently lost—they increase basis of new shares
Example
- Sell 100 shares at $5,000 loss on March 1
- RSUs vest 100 shares on March 15
- Wash sale triggered: $5,000 loss disallowed
- New RSU basis increased by $5,000
- Loss will be realized when RSUs are eventually sold
Capital Loss Limitations
Annual Capital Loss Deduction Limit
You can only deduct $3,000 per year in net capital losses against ordinary income ($1,500 if married filing separately).
Capital Loss Carryforward Rules
Excess losses carry forward indefinitely:
- Maintain their character (short-term vs. long-term)
- Can offset unlimited capital gains in future years
- Can offset $3,000 of ordinary income per year
- Carry forward year after year until fully used
Strategic Implications
Tax Loss Harvesting Considerations:
- Large equity positions may generate significant losses if stock declines
- Those losses may take multiple years to fully utilize
- Consider timing of gains to offset losses in same year
- Carryforwards persist but lose time value of money
Example
Year 1:
- Capital losses: $50,000
- Capital gains: $10,000
- Net loss: $40,000
- Deduct against ordinary income: $3,000
- Carryforward: $37,000
Year 2:
- Capital gains: $15,000
- Use carryforward: $15,000 to offset gains
- Deduct against ordinary income: $3,000
- Remaining carryforward: $19,000
Income Types and Tax Treatment Detail
Understanding how different income types flow through the tax calculation:
| Income Type | Tax Treatment | Rate | Special Considerations |
|---|---|---|---|
| W-2 Wages | Ordinary income | 10%-37% marginal | Subject to FICA taxes |
| RSU Vesting | Ordinary income | 10%-37% marginal | Often under-withheld; subject to FICA |
| NSO Exercise Spread | Ordinary income | 10%-37% marginal | May require estimated payments |
| ISO Exercise - Regular Tax | No immediate tax | N/A | Creates AMT preference item |
| ISO Exercise - AMT | Preference item | 26%-28% AMT rates | May generate future AMT credits |
| Short-Term Capital Gains | Ordinary income | 10%-37% marginal | Held ≤1 year |
| Long-Term Capital Gains | Preferential rates | 0%, 15%, 20% | Held >1 year |
| Qualified Dividends | Preferential rates | 0%, 15%, 20% | Most corporate dividends |
| Self-Employment Income | Ordinary + SE tax | Income tax + 15.3% SE | 50% of SE tax deductible |
FICA Tax Details
Social Security Tax (2025)
Rate: 6.2% (employee) + 6.2% (employer) = 12.4% total
Wage Base Limit: $176,100
Key Points:
- Only applies to earned income (W-2 wages, self-employment)
- Not assessed on investment income or capital gains
- Equity compensation (RSUs, NSO spreads) is subject to Social Security tax
- Once wage base is exceeded, no additional Social Security tax for that year
Medicare Tax (2025)
Standard Rate: 1.45% (employee) + 1.45% (employer) = 2.9% total
Additional Medicare Tax: 0.9% on wages exceeding:
- $200,000 (Single)
- $250,000 (Married Filing Jointly)
- $125,000 (Married Filing Separately)
Key Points:
- No wage base limit—applies to all earned income
- Additional Medicare Tax applies only to employee portion
- Not assessed on investment income (but high-income taxpayers may pay 3.8% Net Investment Income Tax separately)
Self-Employment Tax
Rate: 15.3% (12.4% Social Security + 2.9% Medicare)
Deduction: 50% of self-employment tax is deductible as an adjustment to income
Wage Base: Same $176,100 limit applies to Social Security portion
Special State Tax Considerations
California RSU Sourcing
California has complex rules for RSUs granted while resident but vesting after moving out of state. A portion of the income may still be taxable to California based on:
- Grant date
- Vesting date
- Periods of California residency vs. non-residency
- Requires specialized CPA analysis
Multi-State Situations
When clients work in multiple states or relocate:
- Income may be apportioned between states
- Different states have different rules for equity compensation
- May need to file multiple state returns
- Credit for taxes paid to other states may be available
No State Income Tax States
Some states have no income tax on wages (as of 2025):
- Alaska, Florida, Nevada, South Dakota, Tennessee, Texas, Washington, Wyoming
- New Hampshire (only taxes interest and dividends, not wages)
- Moving to these states can significantly impact tax planning for equity compensation
Tax Law Changes and Updates
How Grantd Stays Current
The Grantd team monitors:
- Annual inflation adjustments to brackets and thresholds
- Legislative changes (e.g., One Big Beautiful Bill Act)
- IRS guidance and rulings
- State tax law changes
Recent Changes - One Big Beautiful Bill Act
SALT Deduction Updates:
- Changes to State and Local Tax (SALT) deduction caps
- Particularly impacts high-tax states (CA, NY, NJ, CT, IL)
- May significantly affect itemized deduction benefits
- Update tax models to reflect current rules
What You Should Monitor
- Annual IRS announcements (typically November/December for following year)
- Major tax legislation
- State legislative changes in high-tax states
- Your Grantd platform will be updated, but verify with CPA
Advanced Planning Strategies
ISO Exercise Timing for AMT Management
Strategy: Exercise ISOs up to but not exceeding AMT threshold
- Calculate AMT crossover point
- Exercise just enough to maximize regular tax benefits
- Avoid triggering excessive AMT
- Spread exercises across multiple years if needed
Capital Gains Harvesting
Strategy: Realize gains in low-income years
- Coordinate with equity compensation timing
- Take advantage of 0% or 15% long-term capital gains rates
- Balance against loss carryforwards
Charitable Giving with Appreciated Stock
Strategy: Donate appreciated shares instead of selling
- Avoid capital gains tax entirely
- Receive charitable deduction for fair market value
- Particularly valuable for highly appreciated positions
- Must hold >1 year for full deduction