1. What Major Changes Did the Tax Cuts and Jobs Act Make to Individual Income Taxes?
The TCJA reduced individual income tax rates across all brackets, increased the standard deduction, and eliminated or limited several personal deductions that had been available under prior law. For most taxpayers, the rate reductions and higher standard deduction meant lower federal income tax liability during the years 2018 through 2025, when individual provisions are scheduled to expire.
The standard deduction nearly doubled. For 2018, the standard deduction rose to $12,000 for single filers and $24,000 for married couples filing jointly, compared to $6,500 and $13,000 respectively under prior law. This increase meant fewer taxpayers needed to itemize deductions, which simplified tax filing for many households.
How Were Personal Deductions Changed under the Tcja?
The Act suspended the personal exemption, which had allowed taxpayers to reduce taxable income by a fixed amount per household member. In exchange, it raised the standard deduction, so the net effect varied by household composition and income level. The TCJA also capped the deduction for state and local taxes (SALT) at $10,000 per year, a change that significantly increased tax liability for high-income taxpayers in high-tax states, such as New York.
Miscellaneous itemized deductions, including investment advisory fees, tax preparation costs, and certain employee business expenses, were suspended entirely. The mortgage interest deduction was limited to interest on up to $750,000 of home acquisition debt, down from $1,000,000 under prior law. These changes mean that many taxpayers who previously benefited from itemizing deductions now find the standard deduction more advantageous.
2. How Did the Tax Cuts and Jobs Act Reshape Corporate and Business Taxation?
The TCJA reduced the corporate income tax rate from 35 percent to a flat 21 percent, a permanent change that applies to all C corporations. For pass-through entities, such as S corporations, partnerships, and sole proprietorships, the Act created a new deduction allowing owners to deduct up to 20 percent of qualified business income (QBI), subject to complex limitations based on W-2 wages paid and the unadjusted basis of business property.
From a practitioner's perspective, the QBI deduction has generated substantial dispute and IRS guidance because the statute's language leaves room for interpretation on what constitutes qualified business income and how the wage and property limitations apply across different business structures. The deduction is temporary and scheduled to expire at the end of 2025, the same date as most individual provisions.
What Is the Qualified Business Income Deduction and When Does It Apply?
The QBI deduction allows eligible taxpayers who own pass-through entities or are self-employed to deduct up to 20 percent of their qualified business income. The deduction is limited to the lesser of the QBI amount or 20 percent of taxable income before the QBI deduction itself. For high-income taxpayers, the deduction phases out based on taxable income thresholds that are adjusted annually for inflation.
The deduction does not apply to certain service businesses, including health, law, accounting, consulting, athletics, and financial services, if the taxpayer's taxable income exceeds the phase-out threshold. These limitations reflect Congressional concern about tax avoidance through aggressive business classification. Taxpayers in affected service industries must carefully document the nature of their business activities and income sources to establish eligibility.
3. What Estate and Tax Planning Considerations Arise from the Tcja?
The TCJA doubled the federal estate and gift tax exemption from $5.49 million per person to $11.2 million per person (adjusted annually for inflation), making it far easier for most estates to avoid federal estate taxation during 2018 through 2025. However, this increase is temporary; the exemption is scheduled to revert to approximately $7 million per person (adjusted for inflation) on January 1, 2026, unless Congress extends or modifies the law.
Taxpayers with substantial wealth should recognize that the current high exemption window creates both opportunity and urgency. Trusts, gifting strategies, and other estate and inheritance tax planning techniques can be deployed now to lock in the higher exemption, but the window is closing. Many families have used this period to make large gifts or establish irrevocable trusts to remove appreciation from their taxable estates before the exemption sunsets.
How Should Taxpayers Prepare for the Expiration of Tcja Provisions?
As 2025 approaches, taxpayers should evaluate the likely impact of TCJA expiration on their tax position. Individual rate reductions and the increased standard deduction will expire, reverting to 2017 levels unless Congress acts. The QBI deduction and the higher estate tax exemption will also expire. Taxpayers with significant business income, substantial estates, or multi-state operations should begin documenting their current tax posture and considering what planning opportunities remain under current law.
Documentation becomes critical during this transition period. Taxpayers should maintain detailed records of basis in business property, W-2 wages paid to employees, and the composition of business income to support QBI deduction claims and to establish the record if disputes arise with the IRS. For those in high-tax states, such as New York, the SALT cap continues to create planning complexity; coordinated state and local tax strategies may help manage combined federal and state tax exposure. Formal engagement with counsel before year-end allows time to structure transactions and make elections that preserve tax efficiency.
4. What Procedural and Compliance Risks Should Taxpayers Monitor?
The TCJA's complexity creates compliance risk. The QBI deduction, in particular, has prompted substantial IRS scrutiny and litigation over what constitutes qualified business income and how wage and property limitations are calculated. In practice, these disputes rarely map neatly onto a single rule, and courts have reached varying conclusions on ambiguous questions.
Taxpayers claiming the QBI deduction should maintain contemporaneous documentation of business structure, W-2 wages, and property basis. The IRS has issued guidance through Treasury regulations, but gaps remain. Documentation timing matters; late or incomplete substantiation of business income sources or wage calculations can weaken a taxpayer's position if examination occurs. Substantiation should be formalized in the tax return itself through proper form completion and supporting schedules, creating a clear record before any audit.
| TCJA Provision | Status | Expiration Date |
| Individual income tax rate reductions | Temporary | December 31, 2025 |
| Increased standard deduction | Temporary | December 31, 2025 |
| Qualified Business Income deduction | Temporary | December 31, 2025 |
| Corporate tax rate (21%) | Permanent | No expiration |
| Doubled estate tax exemption | Temporary | December 31, 2025 |
The table above summarizes which TCJA provisions are permanent and which sunset. As counsel, I often advise clients to use the current high-exemption environment for estate planning while the window remains open, and to begin modeling the tax impact of expiration now rather than facing surprises in 2026. Concrete steps include obtaining a current basis calculation for all business property, reconciling W-2 wage records with payroll systems, and reviewing trust and entity structures to ensure they align with your intended tax outcome under both current law and post-2025 law. Strategic timing of large gifts, income recognition, or entity elections before year-end can meaningfully reduce tax exposure and preserve flexibility for the transition period ahead.
14 May, 2026
