What the Tax Cuts and Jobs Act did

The Tax Cuts and Jobs Act, passed in December 2017, made sweeping changes to how federal income tax works. It lowered tax rates for most income brackets, nearly doubled the standard deduction, eliminated personal exemptions, expanded the child tax credit, and reduced the corporate tax rate from 35% to 21%. For individuals, these changes took effect in 2018. Many of these individual provisions are set to expire at the end of 2025 unless Congress extends them.

Whether the law "worked" depends on what you measure. The law did reduce the amount of federal income tax most people paid in 2018 and the years after. It also changed which deductions and credits were available. But the broader economic effects — whether it spurred growth, whether it paid for itself through increased revenue, whether it affected wages or job creation — remain contested among economists and policy analysts.

Key Takeaways

  • The law lowered individual income tax rates across all brackets and nearly doubled the standard deduction, which reduced taxes for most filers in 2018 and beyond.
  • The law eliminated personal exemptions and changed how many deductions work, so the tax benefit varied widely depending on your income and family situation.
  • Individual tax provisions expire at the end of 2025 unless Congress votes to extend them, which means your tax bill may change in 2026.
  • Economists disagree on whether the law achieved its stated goals of spurring economic growth and job creation, and whether the revenue loss was offset by economic gains.

How the law changed your tax brackets and standard deduction

The law lowered the tax rate in every income bracket. For example, the top rate fell from 39.6% to 37%. The 28% bracket became 24%. The 25% bracket became 22%. These lower rates applied to 2018 through 2025 tax returns.

The standard deduction — the amount you can deduct without itemizing — nearly doubled. For the 2018 tax year, the standard deduction rose to $12,000 for single filers and $24,000 for married couples filing jointly. These amounts increase each year for inflation. Because the standard deduction grew so much, fewer people found it worthwhile to itemize deductions instead.

The law also eliminated personal exemptions, which had allowed you to deduct a fixed amount for yourself and each dependent. This offset some of the benefit from lower rates and a higher standard deduction, especially for large families.

Changes to deductions and credits that affected your return

The law capped the state and local tax deduction (often called SALT) at $10,000 per year. Before the law, there was no cap. This hit people in high-tax states harder than others. The law also limited the mortgage interest deduction to loans of $750,000 or less, down from $1 million.

On the positive side for many families, the child tax credit doubled from $1,000 to $2,000 per child under 17. The income thresholds at which the credit phases out also rose. The law also created a new $500 credit for dependents who do not may have access to for the child tax credit.

The law eliminated or reduced several other deductions: the deduction for personal exemptions, the deduction for moving expenses (except for military members), and the deduction for tax preparation fees. It also changed how the alternative minimum tax works.

What happened to corporate taxes and business income

The law cut the corporate income tax rate from 35% to a flat 21%, effective when ready in 2018. It also created a new 20% deduction for certain business income earned by sole proprietors, partnerships, and S corporations — entities that pass income through to the owner's personal return. This deduction, called the may have access to business income deduction, has income limits and other restrictions.

The law also changed how businesses can deduct the cost of equipment and property. It allowed when ready full deduction (called "expensing") for most tangible property, rather than spreading the deduction over many years. These business provisions do not have an expiration date, unlike most individual provisions.

The debate over whether the law achieved its goals

Supporters of the law argued it would spur economic growth, increase wages, and create jobs by leaving more money in the hands of businesses and individuals. Some pointed to stock market gains and low unemployment in the years after 2017 as evidence the law worked.

Critics and many economists argued the law did not deliver on these promises. They noted that wage growth did not accelerate significantly after the law passed, that much of the corporate tax savings went to stock buybacks rather than wage increases or investment, and that the federal deficit grew substantially. The Congressional Budget Office and other analysts found that the law's long-term economic effects were modest at best.

A third group of economists and analysts focused on the distributional effects: the law reduced taxes more for high-income earners and corporations than for middle-income households, widening the after-tax income gap. Others countered that most taxpayers did see a reduction in their federal income tax bill in 2018 and subsequent years.

What happens when the individual provisions expire in 2026

Unless Congress votes to extend them, most of the individual income tax changes expire on December 31, 2025. This means tax rates will revert to their pre-2017 levels, the standard deduction will drop back to its lower amount, and personal exemptions will return. Your federal income tax bill could rise significantly in 2026 if no action is taken.

The corporate tax rate of 21% and the business income deduction do not have expiration dates, so those changes are permanent unless Congress repeals them separately. This asymmetry — temporary individual provisions and permanent business provisions — was a deliberate choice made during the law's drafting.

How to understand the law's effect on your own taxes

The best way to see how the law affected you is to compare your actual tax bill from 2018 onward with what you would have owed under the old rules. Your tax return itself does not show this comparison. Some tax software allows you to run a "what-if" calculation using pre-2017 rules, but this requires manual entry.

If you want a rough sense, look at your 2017 return and your 2018 return side by side. If your income was similar but your tax bill dropped, the law reduced your taxes. If your tax bill stayed about the same or rose despite similar income, the loss of personal exemptions or the SALT cap may have offset the benefit of lower rates. The effect varied significantly based on income level, state of residence, family size, and whether you itemized deductions.

Frequently Asked Questions

Will my taxes go up in 2026 if Congress does not extend the law?

Yes, unless Congress votes to extend the individual provisions. Tax rates will return to pre-2017 levels, the standard deduction will drop, and personal exemptions will come back. Your federal income tax bill could increase noticeably. Congress may extend the provisions, repeal them, or modify them, but without action, the changes expire automatically.

Did the law reduce taxes for everyone?

Most people saw a reduction in federal income tax in 2018 and after, but not everyone. Some high-income earners in expensive states saw little benefit or even a tax increase because of the $10,000 SALT cap. Families with many dependents lost the personal exemption benefit. The effect depended on your specific situation.

Why do the individual provisions expire but the corporate tax cut does not?

Congress used a budget procedure called reconciliation to pass the law, which allowed it to pass with a straightforward majority in the Senate. Reconciliation rules require provisions that increase the deficit to expire after ten years unless extended. The corporate tax cut was written as permanent, while individual provisions were set to expire, as a deliberate legislative choice.

Did the law pay for itself through economic growth?

This remains disputed. The law reduced federal tax revenue significantly. Supporters argued that economic growth would offset the revenue loss, but most economic analyses found the growth effect was modest and did not fully offset the revenue loss. The federal deficit increased in the years after the law passed.

How do I know if I should itemize or take the standard deduction now?

Compare the two amounts. Add up your deductible expenses — mortgage interest, state and local taxes (capped at $10,000), charitable contributions, and others. If that total exceeds the standard deduction for your filing status, itemize. If not, take the standard deduction. Most people take the standard deduction because it nearly doubled under this law.