Standard Deduction vs Itemized Deductions: How CPAs Decide for Clients in 2025

For the majority of individual tax clients, the 2025 standard deduction wins without running a calculation. The TCJA nearly doubled the standard deduction and installed a $10,000 SALT cap, which together eliminated the primary reason most W-2 employees used to itemize — state income taxes and property taxes once routinely pushed itemized totals above the old threshold. Today, itemizing makes sense primarily for clients with large mortgage interest on high-balance loans, documented medical costs above the 7.5% AGI floor, or charitable giving that alone (or bundled over multiple years) clears the standard deduction threshold. For clients on the borderline, deduction bunching — concentrating two or three years of charitable gifts into one year through a donor-advised fund, then taking the standard deduction in the others — captures the benefit of both strategies and is almost always more efficient than splitting the difference annually.

2025 Standard Deduction Amounts by Filing Status

The standard deduction amounts for 2025, per IRS Rev. Proc. 2024-40 (inflation-adjusted from TCJA base levels):

Clients who are age 65 or older, or blind, receive an additional standard deduction on top of the base amount:

A married couple where both spouses are 65 or older receives $30,000 + $1,250 + $1,250 = $32,500 before itemizing becomes relevant. For many retirees on fixed income with paid-off mortgages, itemizing is structurally impossible at this threshold.

The threshold effect on planning: The standard deduction is an above-the-board minimum. A client with $28,000 in itemized deductions (MFJ) gets $30,000 automatically — itemizing costs compliance effort with zero tax benefit. The CPA's job is not to calculate itemized totals for every client; it is to identify the clients where itemized deductions plausibly exceed the standard threshold, then model precisely.

What Can Still Be Itemized in 2025 — and What Can't

The TCJA restructured itemized deductions substantially. Several categories that routinely drove itemization before 2018 were suspended or capped. As extended by OBBBA, these rules remain in effect for 2025:

The suspension of miscellaneous itemized deductions — which previously included unreimbursed employee expenses, investment advisory fees, tax preparation fees, and union dues — removed a major itemizing driver for W-2 employees. A client who previously deducted $6,000 in unreimbursed business expenses on Schedule A can no longer do so. Those deductions simply do not exist at the federal level for employees under current law.

The SALT Cap: Why Most W-2 Employees Can't Beat the Standard Deduction

Before TCJA, state income taxes and property taxes were fully deductible without limit. In a high-tax state, a client with $15,000 in state income taxes and $8,000 in property taxes had $23,000 in SALT deductions alone — well on their way to itemizing. Today that same client has $10,000 in SALT deductions, regardless of actual state tax burden.

The practical result: a married client in California, New York, or New Jersey who pays $18,000 in state income taxes and $10,000 in property taxes has a $10,000 SALT deduction — identical to a client in Texas with $0 in state income tax and $10,000 in property taxes. Geographic variation in state tax rates no longer affects the federal deduction.

Who the SALT cap does and doesn't affect:

• W-2 employees in high-tax states with mortgages under $400,000: Almost certainly taking the standard deduction. SALT maxes at $10,000; mortgage interest on a $350,000 loan at 6.5% is roughly $22,000 in year 1, declining each year. Total: $32,000 — barely above MFJ standard in year 1, below it within a few years of amortization.
• High earners with large mortgages: A $900,000 mortgage originated after 12/15/2017 at 6.5% generates approximately $57,000 in interest in year 1, limited to interest on $750,000 of acquisition debt (roughly $48,000). Add $10,000 SALT and even modest charitable giving, and itemizing is clearly favorable.
• Retirees with paid-off homes: No mortgage interest, SALT limited to property taxes often well below $10,000. Unless medical expenses are substantial or charitable giving is large, standard deduction wins.
• Pass-through business owners (S-Corps, partnerships): The SALT cap applies at the individual level — but pass-through entities in most states can elect to pay state income tax at the entity level instead, bypassing the cap entirely. This state PTE election is now available in 36+ states and often saves $10,000–$30,000 in federal tax annually for high earners. See How to Use State PTE Tax Elections to Bypass the SALT Cap.

Side-by-Side: Which Strategy Wins for Common Client Profiles

The medical expense deduction is the most volatile variable in this analysis. At a 7.5% AGI floor, a client must incur substantial unreimbursed costs before any deduction is available — and the floor is calculated on AGI, not income above some lower threshold. At $250,000 AGI, the floor is $18,750 in unreimbursed medical costs. Every dollar of eligible expense above that amount is deductible. For clients who face major medical events — cancer treatment, long-term care, significant dental reconstruction — the CPA should run this calculation explicitly for that year rather than assuming the standard deduction.

When to Choose the Standard Deduction

The standard deduction is the right answer when:

• The sum of all itemizable deductions is below the applicable threshold (the most common situation)
• The client is a renter or has a small mortgage with limited interest — SALT alone rarely clears the threshold
• The client is a retiree with a paid-off home and moderate charitable giving
• The client's income is modest enough that the 7.5% medical floor requires catastrophic expenses to produce a deduction
• The client is using Qualified Charitable Distributions (QCDs) from an IRA — QCDs reduce AGI directly regardless of whether the client itemizes, making them more tax-efficient than a charitable deduction for clients near the standard deduction threshold
• The client's W-2 withholding or estimated payments are already calibrated to the standard deduction, and the estimated benefit of itemizing is small enough that it does not justify revisiting the withholding strategy

For self-employed clients: several significant deductions are above-the-line — meaning they reduce AGI before the standard vs itemized choice is even made. The self-employment tax deduction (50% of SE tax), self-employed health insurance premiums, and SEP-IRA or solo 401(k) contributions all reduce AGI directly under IRC §§164(f), 162(l), and 219. A Schedule C client's standard vs itemized analysis applies to what remains after these deductions; frequently, the AGI reduction from above-the-line items is far more significant than itemized deduction optimization. For the full SE tax reduction framework, see How to Minimize Self-Employment Tax for High-Earning Business Clients.

When to Choose Itemized Deductions

Itemizing is clearly the better answer when:

• Mortgage interest is large: Clients with mortgage balances above $400,000–$500,000 in early amortization years will often exceed the MFJ standard threshold when combined with SALT and any charitable giving. Grandfathered pre-2018 loans with balances up to $1,000,000 have even more deductible interest.
• Charitable giving is substantial: A client who gives $25,000+ per year to charity has a structurally strong itemized position when combined with SALT ($10,000) and any mortgage interest.
• Medical expenses are catastrophic: In a year of cancer treatment, organ transplant, or long-term care facility costs, out-of-pocket medical expenses can reach six figures. After the 7.5% floor, the remaining deduction can exceed the standard deduction on its own.
• The client has investment interest expense: Clients who borrow to invest and have net investment income can deduct investment interest against that income on Form 4952 — this is an itemized deduction that has no analog in the standard deduction.

A client who itemizes should also verify that their withholding or estimated tax payments reflect the itemized position — a client who switches from standard to itemized mid-year without adjusting withholding may be overwithholding.

Deduction Bunching: The Strategy for Clients Near the Borderline

Clients whose annual itemized deductions fall between the standard deduction and 150–200% of it are the best candidates for deduction bunching: deliberately concentrating two or three years of discretionary deductible expenses into a single tax year to clear the standard deduction threshold by a meaningful margin, then taking the standard deduction in the off years.

The mechanics (MFJ example):

A married client gives $12,000 per year to charity and has $10,000 in SALT and $8,000 in mortgage interest ($30,000 in itemized annually — exactly equal to the standard deduction). The client gains nothing from itemizing.

With bunching via a donor-advised fund:

• Year 1: Contribute $24,000 to a DAF (two years of charitable giving in one). Itemized total: $42,000 ($24K charitable + $10K SALT + $8K mortgage interest). Deduction above standard: $12,000.
• Year 2: Distribute the prior-year DAF balance to the client's chosen charities, contribute $0 new charitable funds. Itemized total: $18,000. Take the $30,000 standard deduction instead.
• Year 2 tax benefit: $30,000 standard deduction vs $18,000 itemized — standard is better by $12,000.

Net result over two years: the client deducted $42,000 in Year 1 and $30,000 in Year 2, for a total of $72,000. Without bunching, they would have deducted $30,000 in both years ($60,000 total). The bunching strategy produced $12,000 more in total deductions over two years, taxed at the client's marginal rate — at 24%, that is $2,880 in permanent tax savings with no change in actual charitable giving.

DAF contribution rules: Contributions to a donor-advised fund are a charitable deduction in the year of contribution, regardless of when the client instructs the fund to distribute to specific charities (IRC §170; IRS Publication 526). The contribution must be irrevocable — once in the DAF, the funds belong to the sponsoring organization, though the client retains advisory rights over distributions. For high-income clients in windfall years, large DAF contributions of appreciated stock generate a charitable deduction at fair market value with no capital gain recognition on the donated securities.

Other bunchable deductions: Medical expenses and property taxes are less controllable, but some discretion exists. Elective medical procedures can be timed. A client planning a significant dental reconstruction or elective surgery near year-end might schedule the procedure earlier to capture the medical deduction in a year where other itemized deductions make itemizing worthwhile. For the year-end sequencing of charitable bunching alongside S-Corp salary adjustments, QBI phase-out planning, and retirement contributions, see Year-End Tax Planning Checklist for CPAs.

AGI Interactions That Change the Calculation

The standard vs itemized choice does not exist in isolation. Several significant tax provisions depend on AGI — and the choice between standard and itemized deductions does not affect AGI at all. Itemized deductions reduce taxable income from AGI, not AGI itself.

This matters in two specific contexts:

QBI deduction phase-out: The Section 199A deduction phases out based on taxable income — which means itemized deductions (or the standard deduction) directly affect QBI phase-out exposure. A client with $400,000 in AGI and $30,000 in itemized deductions has $370,000 in taxable income — below the $394,600 MFJ phase-out threshold. The same client taking the $30,000 standard deduction has $370,000 in taxable income as well. In this case it doesn't matter. But where itemized deductions meaningfully exceed the standard deduction, itemizing pushes taxable income further below the phase-out threshold, preserving the QBI deduction. For clients near the Section 199A phase-out range, the value of additional itemized deductions includes not just the direct deduction but also any QBI deduction preserved — see QBI Deduction in 2025: How Section 199A Works After OBBBA for the full phase-out calculation.

Roth conversion sizing: A Roth conversion adds to taxable income in the conversion year. If the client itemizes, their pre-conversion taxable income is lower than if they take the standard deduction — creating more bracket space before the next marginal rate tier. A client modeling a bracket-filling Roth conversion should establish the correct standard vs itemized position first, then calculate the available bracket space. Getting this backwards — projecting bracket space before finalizing the deduction strategy — produces an incorrectly sized conversion. For the full conversion framework, see How to Advise Clients on Roth IRA Conversions.

Bottom Line

The 2025 standard deduction is the right answer for most clients — not because itemizing takes effort, but because the arithmetic genuinely does not support it. The SALT cap eliminated the main driver for most W-2 employees, and the doubled standard deduction set a high bar. The CPA's value is not in calculating itemized totals for 200 clients; it is in identifying the 15–20 clients where itemizing is clearly favorable (large mortgages, large charitable giving, catastrophic medical years) and the borderline clients who should be bunching. For the latter group, the deduction bunching math nearly always produces better results than splitting the difference every year — and a donor-advised fund makes it entirely practical.

FAQs

Can a client switch between standard and itemized deductions from year to year?

Yes. Taxpayers may choose either method on any given return and are not locked into the choice from prior years. Married filing jointly and married filing separately filers face one constraint: if one spouse itemizes, the other must also itemize — the standard deduction is not available to the separately-filing spouse when the other itemizes (IRC §63(c)(6)(A)). This is a planning point for couples who file separately.

Does the SALT cap apply per person or per return?

The $10,000 limit applies per return. A married couple filing jointly is limited to $10,000 total across state and local income taxes, state and local sales taxes (in lieu of income taxes), and real property taxes. Married filing separately filers are each limited to $5,000. There is no way to deduct more than $10,000 in SALT on a joint return regardless of how much was actually paid.

Does mortgage interest on a home equity loan qualify as an itemized deduction?

Only if the loan proceeds were used to buy, build, or substantially improve the home securing the loan (IRS Publication 936). Under TCJA (extended by OBBBA), interest on home equity debt used for personal purposes — credit card consolidation, tuition, vehicles — is not deductible, even if the loan is secured by the home. Interest on home equity debt used to substantially improve the home is deductible as acquisition debt, subject to the combined $750,000 acquisition debt cap.

Do state income tax refunds create income in the year received?

Yes, if the taxpayer itemized and deducted state income taxes in the prior year. Under the tax benefit rule (IRC §111), a refund of state taxes that generated a federal itemized deduction in a prior year is taxable federal income in the year of receipt, to the extent the prior-year deduction produced a tax benefit. Clients who took the standard deduction in the prior year have no taxable refund income, because the state tax deduction produced no incremental federal benefit.

Can a client deduct both mortgage interest and real estate taxes if they exceed the SALT cap?

These are separate line items on Schedule A. Mortgage interest (Form 1098) is not subject to the SALT cap. Only state and local income taxes plus property taxes are combined for the $10,000 SALT limitation. A client with $10,000 in property taxes and $35,000 in mortgage interest deducts $35,000 in mortgage interest plus $10,000 in SALT — the property tax is capped as part of SALT, but mortgage interest is uncapped (subject to the $750,000 acquisition debt limit).

What happens when a client has a large charitable deduction that exceeds 60% of AGI?

Contributions to public charities that exceed 60% of AGI in a given year carry forward for up to five years (IRC §170(d)(1)). The excess is deductible in future years subject to the same AGI percentage limits. Clients who make large one-time gifts — appreciated business stock, closely held business interests — should model the multi-year carryforward alongside current-year deductibility to ensure the deduction is fully utilized.

Is it worth itemizing if the total exceeds the standard deduction by only a few hundred dollars?

From a purely tax math perspective, every dollar of deduction above the standard deduction reduces taxable income. A $500 incremental benefit at a 22% marginal rate produces $110 in additional tax savings. Whether the compliance time — gathering receipts, completing Schedule A, verifying mortgage interest statements — is worth $110 is a judgment call. For clients whose situation changes year to year and who are near the borderline, establishing a standard review in the engagement letter avoids missing meaningful opportunities.

Arvori helps CPAs track deduction strategy across their client roster — surfacing clients near the itemized threshold, flagging medical expense years, and modeling bunching scenarios alongside Roth conversions and QBI phase-out exposure. Learn more at arvori.app.