If you earn too much to contribute to a Roth IRA, you've probably heard about the "backdoor" workaround.
Here's the catch: a provision tucked into recent tax law is making that maneuver messier for people who've been doing it on autopilot for years.
You put money into a traditional IRA with after-tax dollars, then convert it to a Roth.
Since you already paid taxes on the money, the conversion itself is usually tax-free.
It's been a legal, widely used strategy for high earners since 2010.
Starting in 2026, new reporting requirements phase in that force brokers to track and report after-tax basis differently than before.
In plain terms, the paperwork you'll get in early 2027 may not match what you filed, and the IRS is expected to flag mismatches automatically.
Because a lot of people who make around $150,000 to $250,000 a year have quietly used this strategy to save for retirement without a work plan.
If your conversion is reported wrong, you could get a letter demanding tax on money that was never actually taxable.
If you have any pre-tax money sitting in a traditional IRA, SEP IRA, or SIMPLE IRA on December 31 of the year you convert, the IRS treats all your IRAs as one pot.
That means a chunk of your "tax-free" conversion becomes taxable.
People with an old 401(k) rollover sitting in an IRA get hit the hardest.
Say you convert $7,000 into a Roth but you also have $50,000 from an old job's 401(k) in a traditional IRA.
Suddenly roughly 88% of that conversion is taxable — a bill that can run into thousands of dollars you didn't plan for.
What can you do right now, before year-end?
First, check every IRA you own, not just the one you're converting.
Log into each account and add up the pre-tax balances.
Second, if you have a big pre-tax IRA and your current employer's 401(k) accepts rollovers, consider moving that money into the 401(k) before December 31.
That clears your IRA pot and can make the backdoor conversion clean again.
Third, if you've been making non-deductible contributions for years, dig up Form 8606 filings.
Missing ones can be filed late, but it's easier to fix now than during an audit.
Fourth, talk to a tax pro before converting, not after.
A $300 conversation beats a $4,000 surprise.
The people most at risk aren't Wall Street types.
They're nurses, teachers, engineers, and small-business owners who maxed out their IRAs and did everything by the book — just not the updated book.
If you're not sure whether this applies to you, the safe move is to pause new conversions until you've checked your IRA balances.
There's no penalty for waiting a few months.
It's just no longer a set-it-and-forget-it move.
Final Thoughts
Treat it like what it is: a tax strategy that needs a yearly checkup, not a one-time setup.