The Hedge
← All modules

M02 · Module 2 of 11

Your real tax picture

Most high earners can name their tax bracket and have no idea what their next dollar of income actually costs them. This module closes that gap by walking through every layer that stacks onto a high earner’s income, so you can read the real rate instead of the headline one.

What you’ll take away

  • Tell the difference between your marginal rate and your effective rate, and know which one matters for a decision.
  • Name the layers that pile onto a high earner’s income beyond the federal brackets.
  • Understand how surtaxes, state tax, and phaseouts push your true next-dollar rate well above your bracket.
  • Spot phaseout cliffs as hidden high-rate zones that punish income inside a narrow band.
  • Know which questions about your own numbers belong with a CFP rather than a calculator.

Marginal rate versus effective rate, and why the gap matters

Two numbers describe your taxes, and they answer different questions.

Your effective rate is your total tax divided by your total income. It is a backward-looking average. If you paid $180,000 of tax on $600,000 of income, your effective rate is 30 percent. That number is useful for understanding the overall bite, and it is the figure people tend to quote when they say “I’m taxed at X percent.”

Your marginal rate is the rate on your next dollar of income. It is forward-looking and decision-relevant. When you weigh a bonus, a Roth conversion, an extra month of consulting work, or whether to defer income to next year, the marginal rate is the number that governs the outcome. The average tells you where you have been. The margin tells you what the next move costs.

High earners routinely misjudge their own marginal rate, and they err in both directions. Some assume it equals their effective rate, which understates it badly: a 30 percent average can sit on top of a 45-plus percent margin once every layer is counted. Others assume it equals their top federal bracket and stop there, which still understates it, because the federal bracket is only the first of several layers. The brackets are progressive, so only the income above each threshold is taxed at that threshold’s rate, never your whole income. That progressivity is exactly why the average lags the margin: your early dollars were taxed lightly, your last dollars are taxed at the top of the stack, and the average smooths the two together.

For nearly every decision you will read about in this curriculum, the marginal rate is the one to reach for. It sets the value of a deduction, the cost of pulling income forward, and the payoff of shifting a dollar from taxable to tax-advantaged. That last point is the through-line of why your marginal rate sets the value of each tax-advantaged dollar: a dollar you keep out of tax is worth your marginal rate, not your average, so the higher your true margin, the more each sheltered dollar is worth.

Federal brackets are only the first layer

Federal ordinary-income tax runs in brackets. Each band of income has its own rate, and you climb through them as income rises. The top ordinary bracket is 37% (2025 and 2026), reached above $768,700 (2026), $751,600 (2025) for a married couple filing jointly. Plenty of high earners sit in the bracket just below the top, paying 35% (2025 and 2026) on their last dollars of wages.

Two details about brackets trip people up.

First, long-term capital gains and qualified dividends ride on a separate schedule with its own rates, topping out at 20% (2025 and 2026) plus a surtax covered below. So a high earner can face one marginal rate on a year-end bonus and a very different one on a stock sale in the same year. When you read “marginal rate,” always ask which kind of income is on the table.

Second, the federal bracket is a floor for your real rate, not the whole story. The layers in the rest of this module sit on top of it. Treating the top bracket as your true marginal rate is the single most common reason high earners underestimate the cost of their next dollar.

Surtaxes that ride on top: NIIT and Additional Medicare

Above certain income levels, two surtaxes attach to your income and stack directly on the brackets.

The Net Investment Income Tax, or NIIT, is a 3.8% (2025 and 2026) tax on investment income (interest, dividends, capital gains, rental income, and similar passive income) once your modified adjusted gross income clears $250,000 (2025 and 2026) for a married couple filing jointly. It applies to the smaller of your net investment income or the amount of income above the threshold. Practically, for a high earner with a taxable brokerage account, NIIT means the real rate on a long-term capital gain is not the headline 20% (2025 and 2026) but 20% (2025 and 2026) plus 3.8% (2025 and 2026). The surtax is easy to forget precisely because it lives on a different line of the return than the capital-gains rate it modifies.

The Additional Medicare Tax is a 0.9% (2025 and 2026) surtax on earned income (wages and self-employment income) above $250,000 (2025 and 2026) for a married couple filing jointly. It sits on top of the regular Medicare tax you already pay, and it lands on the same wage dollars your federal bracket is taxing. For a high-W-2 earner, this means the true marginal rate on the next dollar of salary is the federal bracket plus 0.9% (2025 and 2026), before state tax is even counted.

Neither surtax is large on its own. Their importance is that they stack. A capital gain can carry the top long-term rate plus NIIT; a wage dollar can carry the top federal bracket plus Additional Medicare; and then state tax goes on top of either. Counting each layer is how a “37 percent bracket” becomes a true marginal rate in the mid-to-high 40s.

How phaseouts create stealth tax brackets

Phaseouts are the layer almost nobody sees coming, and they can produce the highest marginal rates of all.

Many tax benefits shrink as income rises. A credit or deduction is available in full at lower incomes, then phases out across a defined income band until it disappears. Inside that band, every extra dollar of income does two things at once: it gets taxed at your ordinary rate, and it claws back a slice of the benefit you were receiving. The clawback acts exactly like additional tax. So your real marginal rate inside the phaseout band is your statutory rate plus the rate at which the benefit is being withdrawn.

A worked sketch makes this concrete. Suppose a benefit phases out over a $50,000 band of income, and the benefit being withdrawn is worth $10,000. Across that band, you lose the benefit gradually as income climbs, which adds an implied rate on top of your bracket for every dollar earned inside the band. A taxpayer whose statutory marginal rate is already high can see a true marginal rate spike well above it for the width of the phaseout, then drop back down once the benefit is fully gone. The result is a stealth bracket: a narrow income range where the next dollar is taxed far harder than the dollars just below or just above it.

Phaseouts hit high earners in several places. Education and family credits phase out as income rises. Certain itemized-deduction benefits and contribution eligibilities phase out. The ability to contribute directly to a Roth IRA phases out entirely above an income threshold, which is its own planning problem covered in backdoor Roth contributions once direct Roth eligibility phases out. The common thread is that the pain is concentrated inside a band rather than spread smoothly, so two households a modest distance apart in income can face very different marginal rates on their next dollar.

Two practical consequences follow. First, the phaseout band is exactly where pulling income forward or pushing it back can change your real rate the most, because crossing into or out of a band moves you between very different marginal rates. Second, because the bands are defined by specific thresholds that shift with indexing and legislation, you cannot eyeball them; this is where a calculator that maps your actual income against the current parameters earns its keep.

A brief word on AMT and state tax

Two more layers complete the stack, and one of them deserves only a brief mention here.

The Alternative Minimum Tax, or AMT, is a parallel tax system. You calculate your tax once under the regular rules and again under the AMT rules, which use a different exemption ($140,200 (2026), $137,000 (2025) for a married couple, itself phasing out at higher incomes) and a different rate structure topping out at 28% (2025 and 2026), and you pay whichever is higher. AMT disallows or adds back certain items that the regular system permits, which is how a taxpayer can owe more under the parallel system than under the regular one. For most high earners with ordinary wage income, AMT is a background consideration. It becomes a front-and-center issue mainly for people who exercise incentive stock options, because the bargain element of an ISO exercise gets added back under the AMT calculation and can generate a large parallel-system bill. That interaction is involved enough to live in its own module: see how AMT specifically interacts with ISO exercises for the full mechanics. The takeaway for this module is narrow: AMT is a second tax system running alongside the first, and a large enough add-back can make it the one you actually pay.

State income tax is the layer that varies most from reader to reader. Some states levy no income tax at all. Others reach a top rate above 13.3% (2025 and 2026), and a few add their own surtaxes on high incomes. Your state rate stacks directly onto everything above: a wage dollar already carrying the top federal bracket plus Additional Medicare also carries your state’s rate, and a capital gain carrying the top long-term rate plus NIIT carries it too. For a high earner in a high-tax state, state income tax can be the difference between a true marginal rate in the low 40s and one approaching or exceeding 50 percent. Because the deductibility of state taxes against your federal return is itself limited and subject to change, you cannot assume state tax is softened by a federal write-off. A move across state lines changes this layer dramatically, and the sourcing rules for deferred compensation and vesting equity make such a move more involved than comparing two headline rates: see state relocation and how a move changes this stack.

Reading your true rate on the next dollar

Stack the layers and the picture comes together. Start with the federal bracket on the relevant kind of income. Add the surtax that applies to that income: NIIT on investment income, Additional Medicare on earned income. Add your state’s rate. Check whether the dollar falls inside a phaseout band, and if it does, add the implied clawback rate. Consider whether AMT is in play. The sum is your real marginal rate, and for a high earner it routinely lands well above the federal bracket alone, sometimes by fifteen points or more once a high-tax state and a phaseout band are both in the mix.

This is also where the line between teaching and personal advice sits. Reading the structure of your own stack is education, and that is what this module and its paired tool are for. Deciding what to do about it (whether to accelerate income into this year, how to time an equity sale around a phaseout, whether a state move pencils out) is a personal decision the platform routes to a CFP. The goal here is that you understand the machinery well enough to have that conversation as an informed participant rather than a passenger.

To see the layers stacked on your own numbers, work through the true marginal rate visualizer. It assembles the federal bracket, NIIT, Additional Medicare, state tax, AMT, and any phaseout cliffs into a single picture of the rate on your next dollar, and it shows you exactly where a cliff spikes that rate inside a band. Seeing the spike is usually the moment the gap between the headline bracket and the real rate stops being abstract.

Putting it together

Your bracket is a starting point, not your real rate. Your effective rate looks backward and your marginal rate looks forward, and almost every decision worth modeling turns on the margin. The true marginal rate is a stack: federal brackets first, then NIIT or Additional Medicare depending on the kind of income, then state tax, then any phaseout clawback, with AMT as a parallel system that can override the whole calculation in specific situations. Phaseouts are the quiet danger, because they bury high marginal rates inside narrow income bands that never show up in a headline bracket table. Once you can read the stack, the rest of the curriculum has a foundation: every dollar you can keep out of this stack is worth your true marginal rate, which is what makes the tax-advantaged moves in later modules worth the effort.

Connections

This module explains how these strategies work. For what to do in your own situation, the platform hands off to a CFP.