AGI Reduction Strategies for High-Income W-2 Families in California and Washington

By Kevin Luu, Co-Founder and Chief Learning Officer. Reviewed on 2026-09-30.

For a W-2 family, the AGI reduction strategies that actually work are the ones that keep income off your W-2 in the first place: pre-tax 401(k) deferrals, HSA and dependent care contributions through payroll, commuter benefits, a nonqualified deferred compensation election if your employer offers one, and net capital losses of up to $3,000 a year. Mortgage interest, charitable gifts, state taxes and the standard deduction do not lower AGI at all; they come off later, after AGI is calculated. For a $1 million household in California, the payroll levers plus a $3,000 harvested capital loss can move about $72,000 out of AGI in 2026, which is worth roughly $34,000 in federal and state tax that year.

This guide is for dual-income families earning $750,000 to $3 million in salary, bonus and RSUs, usually with young kids, living in California or Washington. The rules are federal, but the value of each lever changes a lot depending on which of those two states you file in.

What AGI is, and why most “deductions” do not touch it

Adjusted gross income is your total income (wages, RSU vests, interest, dividends, capital gains) minus a short list of “above-the-line” adjustments. It is line 11a of the 2025 Form 1040. Everything else people call a deduction, including the standard deduction, SALT, mortgage interest and gifts to a donor-advised fund, is subtracted after AGI to reach taxable income.

That distinction answers several common questions:

• Do 401(k) contributions reduce AGI? Traditional (pre-tax) deferrals do, because they never appear in box 1 of your W-2. Roth 401(k) deferrals and after-tax contributions for a mega backdoor Roth do not.
• Do FSA contributions reduce AGI? Yes. Health FSA and dependent care FSA dollars run through your employer’s cafeteria plan and are left out of box 1 wages.
• Can investment interest expense reduce AGI? No. Margin interest is an itemized deduction on Schedule A (figured on Form 4952), so it lowers taxable income, not AGI.
• Do 529 contributions reduce AGI? No, federally or in California. California allows no deduction for 529 contributions for 2026.

Why AGI matters less, and more, at a $1 million income

Most AGI advice is written for households trying to get under an income limit for a credit. At this income, those limits are already far behind you. For 2026, the Child Tax Credit of $2,200 per child phases out starting at $400,000 of modified AGI for joint filers and is gone for a two-child family at $488,000. The SALT cap of $40,400 shrinks by 30% of MAGI above $505,000 and hits its $10,000 floor at about $606,333. Direct Roth IRA contributions phase out between $242,000 and $252,000. Trimming $72,000 from a $1 million AGI changes none of these.

What it does change is tax at your top marginal rate. For 2026, joint filers pay 37% federal on taxable income over $768,700. In California, the 2025 brackets (2026 schedules were not yet published when this was reviewed) put joint income between $891,542 and $1,485,906 at 11.3%. So every dollar you keep out of AGI saves close to 48 cents that year.

Three lines are worth watching because a lower AGI can still cross them:

• California’s 1% Behavioral Health Services Tax applies to taxable income over $1,000,000, the same threshold for joint filers. A joint filer just above it is in the 11.3% bracket, so each dollar brought back under $1,000,000 saves 12.3% in California (11.3% plus 1%).
• Washington’s new income tax: 9.9% on AGI over $1,000,000, starting January 1, 2028 (SB 6346, per the Washington Department of Revenue). Washington has no wage income tax in 2026, but AGI will matter there within two tax years.
• The 37% federal bracket. A couple with taxable income near $768,700 saves 37% only on the dollars above it, and 35% below.

The levers that lower AGI for W-2 families in 2026

Pre-tax 401(k) deferrals: the biggest line, but a timing choice

Two spouses each deferring $24,500 pre-tax keep $49,000 out of AGI for 2026. This is a deferral, not a write-off: the money is taxed as ordinary income when withdrawn. The real question is whether your rate in retirement will be lower than 37% federal plus 11.3% in California today. At this income, pre-tax often comes out ahead, and a family planning to retire in Washington or another no-income-tax state has an even stronger case. Families who expect large pensions, deferred comp payouts and required distributions may prefer to split between pre-tax and Roth. The retirement and employee benefits review is where we weigh that choice.

One rule to know: if you earned more than $150,000 in FICA wages from your employer in 2025, any 2026 catch-up contributions (age 50+) must go in as Roth, so they will not lower AGI.

HSA: strong federally, weaker in California

A family HSA contribution of $8,750 through payroll lowers federal AGI and can be invested for decades. California does not conform: the FTB’s Schedule CA (540) instructions tell you to add back the HSA amount in W-2 box 12, code W, and HSA earnings are taxable in California each year. In Washington, the HSA works as intended. If you are weighing an HDHP mainly for the HSA, compare the full premium and deductible picture first; our guide to high-deductible plans for families covers that trade.

Dependent care FSA: the parents-of-young-kids lever

For tax years starting in 2026, the federal dependent care FSA limit rose to $7,500 per household (from $5,000), but only if your employer’s plan adopts it. With preschool, after-school care or summer day camp for kids under 13, most families here will spend that easily. California generally does not conform to the 2025 federal law that raised the limit, so treat the extra $2,500 as possibly taxable in California until the FTB says otherwise.

Deferred compensation: the only way to shrink a large bonus year

Many large employers offer a nonqualified deferred compensation plan to senior staff. You elect to defer salary or bonus, and that pay stays out of your W-2 and AGI until the plan pays it out, often over several years after you leave. Under IRC §409A, the election generally has to be made before the year in which you earn the pay. The trade-off is real: deferred amounts are an unsecured promise from your employer, so a family with most of its net worth already in employer RSUs is adding more exposure to the same company.

RSUs themselves offer no AGI lever. They are taxed as wages when shares are delivered at vest, and an 83(b) election is not available for RSUs. Employers often withhold at the optional 22% federal flat rate on supplemental wages (37% is mandatory on supplemental wages above $1,000,000 in the year), which is usually less than the tax owed at the 35% and 37% brackets. What you can control is everything around the vest: the payroll levers above, and selling shares promptly so the vest does not also become a concentrated position.

Tax-loss harvesting: small against wages, bigger against gains

Net capital losses offset capital gains without limit, and up to $3,000 a year of ordinary income ($1,500 if married filing separately), with the rest carried forward (IRS Topic 409). Against wages, $3,000 is modest. Against gains from selling vested company stock, harvested losses can offset far more. In California, capital gains are taxed as ordinary income with no lower rate, so a harvested loss that offsets a gain saves the full state rate too. In Washington, gains above the capital gains tax standard deduction ($278,000 for 2025, the latest published) are taxed at 7% (9.9% on taxable gains above $1,000,000, from 2025 onward), so harvesting matters there only for families with large sales.

What does not lower AGI, despite what you may have read

• Holding investments longer. Long-term gains get a lower federal rate, but they are still fully included in AGI.
• Education credits. They are credits, not adjustments, and phase out far below this income.
• Municipal bonds keep interest out of AGI, but the income is added back in several MAGI tests, so they are an investment choice, not an AGI strategy.
• Giving to a donor-advised fund. It is an itemized deduction. Useful, but it lowers taxable income, not AGI.

Worked example: a $1 million W-2 household in California

Assumptions (illustrative): married filing jointly, both spouses under 50, $1,000,000 of combined W-2 pay including RSU vests, two children ages 4 and 7 in preschool and after-school care, one spouse on a family HDHP, $50,000 of federal itemized deductions and $30,000 of California deductions. Figures are 2026 federal limits and 2025 California brackets.

Federal AGI falls from $1,000,000 to $927,670 and taxable income from $950,000 to $877,670, still above the 37% line, so every dollar saves 37%. In California, $61,080 at 11.3% saves about $6,902. Combined, about $33,664 less tax for 2026, most of it by filling out benefit elections during open enrollment.

If the same family also defers $60,000 of bonus into a deferred compensation plan, federal taxable income drops to $817,670 (still in the 37% bracket), saving another $22,200 federal, plus about $6,350 in California (part at 11.3%, part at 10.3%). That tax is postponed, not forgiven: it comes due when the plan pays out.

The same family in Washington gets the same $26,762 federal saving, pays no state income tax on wages in 2026, and gets full use of the HSA. From 2028, if their AGI is above $1,000,000, each dollar they keep below that line also avoids Washington’s 9.9% tax.

The decision you actually have to make each year

1. Open enrollment (often in the fall): set the 401(k) percentage so each spouse reaches $24,500, confirm the dependent care FSA amount, choose the HDHP only if the math works without the HSA story, and turn on commuter benefits.
2. Deferred comp election window: decide how much of next year’s bonus to defer, knowing it is tied to your employer’s credit.
3. Before year end: review taxable accounts for losses to harvest, especially in a year you sold vested shares.
4. RSU vest months: check whether 22% withholding leaves a balance due and adjust estimated payments.

Common mistakes we see

• Choosing Roth 401(k) by default at a 48% combined marginal rate, without a reason to expect a higher rate later.
• Assuming a deductible IRA contribution is available. At this income, with a workplace plan, it is not; the non-deductible IRA route is a different tool.
• Counting the HSA as a California deduction.
• Leaving the dependent care FSA at $5,000 after the employer raised the plan limit.
• Mixing up the tests. Some limits use AGI, others use MAGI with add-backs; our guide on reducing MAGI covers the difference.

What to write down for your kids

Children see the paycheck and the house. They do not see the open-enrollment form where their parents chose to defer $49,000 of income, or why. A one-page note each year (what you elected, what it saved, and why you chose pre-tax over Roth) becomes part of your FamilyKnowledge® Library. As Kevin Luu puts it: “Your kids will inherit your money. Will they inherit your judgment?” Our Age Five Wealth Education work helps families start that record early.

Frequently asked questions

Does the standard deduction lower AGI?

No. The standard deduction ($32,200 for joint filers in 2026) is subtracted after AGI to reach taxable income. So are itemized deductions like mortgage interest and SALT. Only above-the-line adjustments, such as HSA contributions and educator expenses, and income that never reaches your W-2, like pre-tax 401(k) and FSA dollars, reduce AGI itself.

Is lowering AGI worth it if we are over every phase-out anyway?

Usually yes, because the benefit at this income comes from the marginal rate, not from a credit. At 37% federal and 11.3% in California, each dollar kept out of AGI saves about 48 cents in 2026. The exceptions are deferrals you expect to be taxed at a higher rate later, which is why the pre-tax versus Roth choice deserves a real look.

Can we lower AGI by giving more to charity?

Not for most working families. Cash and stock gifts, including to a donor-advised fund, are itemized deductions that reduce taxable income after AGI. Giving appreciated shares instead of cash also avoids realizing the gain, so it keeps that gain out of AGI, which is the one way giving touches AGI for W-2 families.

Next step

Before your next open enrollment, pull last year’s W-2s and check boxes 1 and 12 for both spouses. If box 1 is close to your total pay, the levers above are unused. If you want a second set of eyes on the whole picture, including RSUs and deferred comp, our Tax & Wealth Assessment is where Age Five Family Office™ starts with new families.

This is general education, and the right move depends on the family’s full picture.

Written by

Kevin Luu

Co-Founder and Chief Learning Officer, Bright Advisers

Kevin has advised high-income W-2 tech and biotech families since 2015, and leads the education-first Age Five Family Office from Brea, California.

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