The Ultimate Guide to State and Local Taxes (SALT)

LEGAL DISCLAIMER: This article provides general, informational content for educational purposes only. It is not a substitute for professional legal advice from a qualified attorney. Always consult with a lawyer for guidance on your specific legal situation.

Imagine your total annual income is a large pizza. Before you can enjoy it, the federal government takes a few slices for federal taxes. But that's not the only hand reaching for a piece. Your state and city governments also take slices for things like schools, roads, and police—these are your State and Local Taxes, or SALT. For decades, the federal government gave you a small break: when calculating your federal tax bill, you could subtract—or “deduct”—the amount you paid in SALT. This meant the federal government would only tax the pizza you had *left* after your state and city took their share. But in 2017, a major law changed the rules. It put a $10,000 “cap” on that deduction. Now, no matter how many slices your state and city take, you can only tell the federal government about $10,000 worth of them. If you live in a state with high taxes and paid, say, $25,000 in SALT, this change meant your federal tax bill could suddenly be much higher. This single rule, the “SALT cap,” became one of the most debated tax policies in recent memory, impacting millions of homeowners and high-earners, particularly in states like California, New York, and New Jersey.

• The Core Concept: State and Local Taxes (SALT) are taxes you pay to your state, county, or city governments, primarily including property_tax, state income_tax, and sometimes sales_tax.
• The Federal Impact: For decades, you could deduct the full amount of SALT you paid from your federally taxable income if you chose to itemize, but the tax_cuts_and_jobs_act_of_2017 limited this deduction to a maximum of $10,000 per household per year.
• Your Bottom Line: This SALT cap means that if your combined state property and income (or sales) taxes exceed $10,000, you may face a higher federal tax bill than you did before 2018, significantly affecting your decision between taking the standard_deduction or itemized_deduction.

The idea that you shouldn't be taxed twice on the same dollar is a long-standing principle in U.S. tax policy. The federal income tax was established in 1913 with the ratification of the sixteenth_amendment. From the very beginning, the law allowed taxpayers to deduct the taxes they paid to state and local governments. The logic was simple: money paid to your state was no longer your income, so the federal government shouldn't tax it. For over a century, this deduction was unlimited. It was a cornerstone of American federalism, acknowledging the shared power and financial needs of different levels of government. This system favored residents of states that provided more public services, which were funded by higher taxes. A resident of New York, for example, might pay high state income and property taxes, but the unlimited federal deduction softened the blow. This effectively meant the federal government was subsidizing high-tax states, as those states' residents could lower their federal tax bills. This all changed dramatically with the passage of the Tax Cuts and Jobs Act of 2017 (TCJA). Proponents of the TCJA argued that the unlimited SALT deduction was an unfair subsidy for wealthy taxpayers in high-tax (often Democratic-led) states, paid for by taxpayers in lower-tax states. To address this, they introduced a simple but powerful change: a $10,000 cap ($5,000 for married individuals filing separately) on the amount of state and local taxes that could be deducted. This single provision instantly became one of the most controversial elements of the new law, sparking political and legal battles that continue to this day.

The primary law governing the SALT deduction is found within the U.S. internal_revenue_code (IRC). The key section was amended by the TCJA.

• Pre-TCJA Law: Before 2018, IRC Section 164 allowed individuals who itemized their deductions to deduct several types of state and local taxes without a specified limit. This included state and local income taxes, real property taxes, and personal property taxes. Taxpayers could also choose to deduct state and local sales taxes instead of income taxes—a benefit for those in states with no income tax.
• The TCJA Amendment (26 U.S. Code § 164(b)(6)): The tax_cuts_and_jobs_act_of_2017 added a new limitation. The most relevant language states:

> “…the aggregate amount of taxes taken into account… for any taxable year shall not exceed $10,000 ($5,000 in the case of a married individual filing a separate return).” Plain-Language Explanation: This legal language establishes the “SALT cap.” It means that when you add up all your eligible state and local taxes for the year (property taxes + income or sales taxes), the total amount you can use as a deduction on your federal tax return is limited to $10,000. Any amount you paid over $10,000 cannot be used to lower your federal taxable income. This cap is scheduled to expire on December 31, 2025. If Congress does not act, the unlimited SALT deduction is set to return in 2026.

The $10,000 SALT cap does not affect everyone equally. Its impact depends heavily on where you live and your income level. A homeowner in a high-tax state like New Jersey might easily pay over $10,000 in property taxes alone, while a resident of a state with no income tax and low property taxes might never reach the cap.

Understanding what counts as “SALT” is the first step to figuring out your deduction. Not every payment to a state or local government qualifies. The internal_revenue_service_(irs) has specific rules.

This is the tax your state and sometimes your city or county levies on your wages, salaries, and other forms of income.

• What's Included:
  • Taxes withheld from your paycheck throughout the year (shown on your w-2_form).
  • Estimated tax payments you made directly to your state or locality.
  • Any overpayment from the previous year's state tax return that you chose to apply to the current year's taxes.
• Relatable Example: Sarah is a graphic designer in Oregon. Her W-2 shows that $8,500 was withheld for Oregon state income tax during the year. This entire $8,500 counts toward her SALT deduction limit.

This is the annual tax you pay on the assessed value of your real estate (and sometimes certain high-value personal property, like a boat or RV). This is often the largest tax payment for homeowners.

• What's Included:
  • Taxes paid on your primary home, vacation homes, and land.
  • Taxes are only deductible in the tax year they are actually paid to the taxing authority, not just when they are billed.
• What's Not Included:
  • Payments for specific services, like trash collection or water, even if they appear on your property tax bill.
  • Special assessments for local benefits, like building a new sidewalk in front of your house.
• Relatable Example: The Miller family lives in Illinois and their annual property tax bill is $12,000, which they pay in two installments. The full $12,000 they pay during the year is eligible for the SALT deduction, but they will be limited by the $10,000 cap.

You have a choice: you can deduct EITHER your state and local income taxes OR your state and local sales taxes. You cannot deduct both.

• Who Chooses This?: This option is primarily for residents of the handful of states with no income tax, like Texas, Florida, Washington, and Nevada.
• How to Calculate: You can either:
  • Keep all your receipts for the entire year and add up the total sales tax you paid (which is highly impractical).
  • Use the IRS's Sales Tax Deduction Calculator or the optional sales tax tables in the schedule_a_(form_1040) instructions. This gives you a standard amount based on your income and location, which you can then add the sales tax paid on large purchases like a new vehicle or boat.
• Relatable Example: David lives in Washington state, which has no income tax. He buys a new car and pays $3,000 in sales tax. He can use the IRS tables to find the standard sales tax deduction for his income level (let's say it's $1,200) and add the $3,000 from the car purchase for a total sales tax deduction of $4,200.

This is the overarching rule that governs all the components above.

• The Golden Rule: After you add up your property taxes and your income taxes (or sales taxes, if you choose that option), the TOTAL you can deduct on schedule_a_(form_1040) cannot exceed $10,000 per household.
• Example Calculation: Maria lives in New Jersey. She paid $14,000 in property taxes and had $9,000 withheld for state income taxes. Her total SALT paid is $23,000. However, due to the cap, when she files her federal tax return, she can only deduct $10,000. The remaining $13,000 she paid in SALT provides her with no federal tax benefit.

• The Taxpayer: That's you. You are responsible for keeping records of taxes paid and for accurately calculating and claiming your deduction.
• Internal_Revenue_Service_(IRS): The federal agency that sets the rules for the SALT deduction (as dictated by Congress) and processes your federal tax return. They provide the forms (like irs_form_1040 and Schedule A) and the instructions for claiming the deduction.
• State Taxing Authorities: (e.g., California Franchise Tax Board, New York State Department of Taxation and Finance). These are the agencies that collect your state income or sales taxes. The amounts you pay them are what you claim on your federal return.
• Local Tax Assessors/Collectors: These are your county or municipal officials who determine the value of your property and collect your property taxes.
• Tax Professionals: (e.g., certified_public_accountant_(cpa), Enrolled Agents, Tax Attorneys). These professionals help you navigate the complexities of tax law, determine whether to itemize, and ensure you are correctly applying the SALT cap.

Navigating the SALT deduction can feel daunting, but a systematic approach makes it manageable. Here’s how to tackle it during tax season.

Before you can do any calculations, you need the right documents.

1. For Income Taxes: Look for your w-2_form, which will show the total amount of state and local income tax withheld in Box 17. If you made estimated payments, you'll need records of those checks or electronic transfers.
2. For Property Taxes: Find your annual property tax bill or records of your payments (like canceled checks or mortgage statements). Your mortgage statement (Form 1098) will often show the amount of real estate tax paid from your escrow account.
3. For Sales Taxes (if applicable): If you live in a no-income-tax state and plan to deduct sales tax, you'll need receipts for any major purchases (cars, boats, RVs, home building materials).

Add up all the eligible taxes you paid during the calendar year.

1. Formula: (State/Local Income Taxes Paid) + (Real Property Taxes Paid) = Total SALT.
2. Alternative Formula: (State/Local Sales Taxes Paid) + (Real Property Taxes Paid) = Total SALT.
3. Example: You paid $11,500 in property taxes and $7,000 in state income taxes. Your total SALT is $18,500.

This is the most critical decision point. You can either take the standard deduction (a fixed dollar amount that anyone can take) or itemize your deductions (listing out all eligible expenses, like SALT, mortgage interest, and charitable contributions).

1. Action: Compare your total potential itemized deductions (including your capped $10,000 SALT) to the standard deduction amount for your filing status.
   • For 2024, the standard deduction is $14,600 for single filers and $29,200 for married couples filing jointly.
2. Rule of Thumb: If your total itemized deductions (SALT capped at $10k + mortgage interest + charity, etc.) are less than your standard deduction, you should take the standard deduction. The SALT cap pushed millions of taxpayers into this category.

If itemizing is still the better choice for you, you must apply the cap.

1. On schedule_a_(form_1040), there is a line for “State and local taxes.”
2. Even if your total SALT from Step 2 was $18,500, you can only enter $10,000 on this line. This is the maximum legal deduction.

In response to the federal SALT cap, some high-tax states have created legal workarounds. The most common is the Pass-Through Entity Tax (PTET).

1. What it is: This allows owners of pass-through businesses (like S-corporations and partnerships) to pay state income tax at the *entity level* rather than the *personal level*. This payment is then fully deductible for the business as a business expense at the federal level, bypassing the individual $10,000 SALT cap. The owner then receives a credit on their state income tax return.
2. Action: If you are a small business owner, talk to a tax professional to see if your state offers a PTET and if it would be beneficial for you. This is a complex area of tax law and is not a DIY project.

• irs_form_1040 (U.S. Individual Income Tax Return): This is the main federal tax form. It's where you will ultimately report your taxable income after taking either the standard or itemized deduction.
• schedule_a_(form_1040) (Itemized Deductions): This is the form you must fill out if you choose to itemize. Lines 5a through 5e are where you report your state and local taxes and apply the $10,000 cap. You will attach this form to your Form 1040.
• w-2_form (Wage and Tax Statement): Your employer sends you this form. Box 17, “State income tax,” is the official record of state income taxes withheld from your pay.

The modern SALT debate was not shaped by a court case, but by a single, sweeping piece of legislation and the legal challenges that followed.

• The Backstory: In 2017, the Republican-controlled Congress and the Trump administration sought to pass the most significant tax reform in decades. Key goals included lowering the corporate tax rate and simplifying the tax code for individuals. A major part of “paying for” these cuts involved eliminating or limiting various tax deductions. The unlimited SALT deduction was a prime target.
• The Legal Question/Policy Debate: Was the unlimited SALT deduction a fair reflection of federalism, or was it an unfair subsidy for high-tax states that forced lower-tax states to foot the bill? Proponents of a cap argued for the latter, claiming it would make the tax code more equitable across all states. Opponents argued the cap was a politically motivated attack on “blue” states that would result in double taxation and damage state and local governments' ability to raise revenue for essential services.
• The Holding/Result: The tax_cuts_and_jobs_act_of_2017 was passed and signed into law. It instituted the $10,000 SALT deduction cap, effective from tax year 2018 through 2025. It also nearly doubled the standard deduction, a strategic move that ensured many taxpayers who lost the full SALT deduction would not see a tax increase because they would no longer itemize anyway.
• Impact on You Today: This act is the sole reason for the $10,000 cap. It fundamentally changed the calculus for millions of American taxpayers, especially middle-class homeowners in coastal states. It forces you to perform the annual analysis of whether itemizing your deductions is still more beneficial than taking the much larger standard deduction.

• The Backstory: Shortly after the TCJA was passed, a coalition of high-tax states, including New York, Connecticut, Maryland, and New Jersey, filed a lawsuit against the federal government. They argued that the SALT cap was unconstitutional.
• The Legal Question: The states argued that the cap unconstitutionally infringed on their sovereign authority to make their own tax and policy decisions. They claimed it was a form of coercive federalism that would cripple their ability to fund state operations. They also argued it departed from a century of accepted tax practice.
• The Court's Holding: The U.S. District Court for the Southern District of New York dismissed the lawsuit. The judge ruled that states do not have a constitutional right to any particular federal tax deduction for their citizens. The court found that Congress has broad power to tax and that the SALT cap fell within that power. The decision was later upheld by the U.S. Court of Appeals for the Second Circuit in 2021, and the supreme_court_of_the_united_states declined to hear the case, effectively ending the direct constitutional challenge.
• Impact on You Today: This ruling solidified the SALT cap as the law of the land (at least until it expires). It confirmed that the only way to change the cap is through an act of Congress, not through the courts. This shifted the fight from the courthouse to the halls of Congress.

The SALT cap remains one of the most politically divisive tax issues. The debate is ongoing and fierce.

• Arguments for Repealing the Cap (or Raising It):
  • Unfair Double Taxation: Proponents of repeal argue that the cap forces residents to pay federal income tax on money they already paid to their state and local governments.
  • Harms Middle-Class Homeowners: While often framed as a “rich people's problem,” many middle-class families in high-cost-of-living areas are hit by the cap.
  • Undermines State Sovereignty: Opponents claim the cap penalizes states that choose to provide more robust public services, interfering with their fiscal decisions.
• Arguments for Keeping the Cap:
  • Tax Fairness: Supporters argue the cap corrects an imbalance where low-tax states were subsidizing high-tax states.
  • Progressive Tax Policy: Keeping the cap primarily affects higher-income households, and repealing it would overwhelmingly benefit the wealthy. According to the Brookings Institution, over 96% of the benefit from a full repeal would go to the top 20% of earners.
  • Fiscal Responsibility: Repealing the cap would be extremely expensive, reducing federal tax revenue by hundreds of billions of dollars that would need to be made up elsewhere.

The future of the SALT deduction is uncertain and tied to several key trends.

• The 2025 “Fiscal Cliff”: The most significant event on the horizon is the scheduled expiration of the SALT cap on December 31, 2025. If Congress does nothing, the deduction reverts to being unlimited for the 2026 tax year. This creates enormous political pressure for a legislative compromise before that date. The outcome of the 2024 elections will almost certainly determine the cap's fate.
• The Rise of Remote Work: The post-pandemic shift to remote work has created immense complexity for state taxation. Individuals may live in one state while working for a company in another, raising questions about which state has the right to tax their income. This “telecommuter tax” issue complicates a person's SALT calculation and could lead to more interstate legal battles.
• State-Level Innovation (PTETs): The proliferation of Pass-Through Entity Tax (PTET) workarounds is a direct response to the federal cap. We can expect more states to adopt these measures. The irs has largely given its blessing to these structures, but it may issue further guidance that could either broaden or restrict their use in the coming years.

• adjusted_gross_income_(agi): Your gross income minus certain “above-the-line” deductions; a key figure in tax calculations.
• ad_valorem_tax: A tax based on the assessed value of an item, such as real estate; property tax is a type of ad valorem tax.
• deduction: An expense that can be subtracted from your taxable income, lowering the amount of income subject to tax.
• federalism: The U.S. system of divided power between a central federal government and individual state governments.
• internal_revenue_code_(irc): The main body of domestic statutory tax law in the United States.
• itemized_deduction: A list of specific eligible expenses, including SALT, that a taxpayer can claim to reduce their taxable income, instead of taking the standard deduction.
• pass-through_entity_tax_(ptet): A state tax levied on a business, allowing it to bypass the federal $10,000 SALT cap for its owners.
• property_tax: A tax paid on the value of real estate, collected by local governments to fund schools, police, and public works.
• sales_tax: A tax paid on the sale of goods and services.
• schedule_a_(form_1040): The IRS form used to report itemized deductions.
• standard_deduction: A fixed-dollar amount that taxpayers can subtract from their income if they choose not to itemize deductions.
• tax_cuts_and_jobs_act_of_2017: The landmark 2017 legislation that created the $10,000 SALT deduction cap.
• tax_liability: The total amount of tax owed to a taxing authority like the IRS.
• w-2_form: The form an employer must send to an employee and the IRS at the end of the year, reporting the employee's annual wages and taxes withheld.

• itemized_deduction
• standard_deduction
• property_tax
• income_tax
• tax_cuts_and_jobs_act_of_2017
• internal_revenue_service_(irs)
• federalism