In 2017, Congress passed the Tax Cuts and Jobs Act and quietly set a time bomb: most of its provisions were written to expire after 2025. For eight years, millions of households benefited from a higher standard deduction, lower rates, and a doubled child tax credit — without knowing any of it was temporary. 2026 is the year the clock ran out. What Congress ultimately did about it — extended everything, let it lapse, or cut a partial deal — will have been settled by the time you read this. What matters now is understanding which provisions affect your household and what you can actually do.
Note: Tax law is actively in flux. The situation may have changed after this article was written. Consult a CPA for your specific 2026 tax situation.
The Standard Deduction: The Change That Hits Most People
The TCJA nearly doubled the standard deduction — from about $6,500 to $13,850 for single filers (inflation-adjusted figures). This is the change that affected the most people, because it meant that itemizing deductions became less beneficial for the majority of taxpayers. About 90 percent of filers stopped itemizing and just took the standard deduction.
If the higher standard deduction expires without renewal, it reverts to roughly pre-2018 levels (inflation-adjusted). For a married couple filing jointly, that's a potential drop from roughly $29,200 to about $16,000 in the standard deduction. This increases taxable income — and therefore the tax bill — for millions of households.
For 40-somethings who own homes and pay mortgage interest and property taxes, a lower standard deduction may make itemizing worthwhile again. But that only helps if your total itemizable deductions actually exceed the new lower threshold.
The Child Tax Credit
The TCJA doubled the child tax credit from $1,000 to $2,000 per qualifying child and expanded who could claim it. If the provision reverts, it drops back to $1,000. For households with children — which describes many people in their 40s — this could mean hundreds to thousands of dollars more in taxes, depending on family size.
Tax Brackets and Rates
The TCJA created somewhat lower and restructured brackets. If rates revert, the top rate rises from 37 percent to 39.6 percent, and some brackets shift. Most people in the middle of the income distribution would see a modest increase in their effective rate. For high earners — particularly those in the $200,000–$500,000 range — the impact is more significant.
The Pass-Through Deduction (If You're Self-Employed)
One TCJA provision that often flies under the radar is the Section 199A deduction — a 20 percent deduction on qualified business income for self-employed people and small business owners. If this expires, freelancers, consultants, and small business owners will see a significant increase in their effective tax rate. For 40-somethings doing any kind of self-employed work, this is worth knowing about.
What You Can Actually Do
Regardless of exactly what Congress did with the TCJA, there are moves that make sense in a higher-tax environment:
Maximize retirement contributions. Money going into a 401(k) or traditional IRA reduces your taxable income dollar-for-dollar. In a higher-rate environment, the value of that deduction increases. For 2026, check the current contribution limits — and if you're 50 or older, catch-up contributions allow you to put in significantly more than the standard limit.
Check your W-4 withholding. If your tax situation changed — new child, changed income, changed deduction picture — your withholding may be off. A surprise tax bill in April is avoidable if you adjust now.
If you're self-employed, talk to a CPA immediately. The pass-through deduction situation specifically affects you, and planning opportunities for the 2026 tax year close when the calendar does.
Consider a tax projection. A CPA can run the numbers under current law for your specific situation. The cost of an hour of professional tax advice is almost always worth it compared to the cost of an unpleasant surprise at filing time.
HSA contributions. Health Savings Accounts are triple tax-advantaged — contributions reduce taxable income, growth is tax-free, and withdrawals for qualified medical expenses are tax-free. In 2026, the contribution limit is $4,300 for self-only coverage and $8,550 for a family plan. If you have a high-deductible health plan and aren't maxing your HSA, that's one of the most efficient tax moves available — especially when rates are under pressure.
The Honest Bottom Line
Tax law is legitimately complicated right now, and 2026 is one of the messier years in recent memory. Don't rely on headlines, which consistently oversimplify what passed and what didn't. Go to IRS.gov for the actual numbers, or pay a CPA for one hour of their time — it costs $150–300 and will almost certainly save you more than that in avoided surprises. Whatever the final law says, the plays that reduce taxable income stay the same: retirement contributions, HSA deposits, deductible business expenses. The magnitude of the benefit shifts; the direction doesn't.