NIIT Avoidance for Retirees

Why does a retiree with no job keep paying a tax built for high earners? Because the net investment income tax doesn’t care whether you work. The NIIT is a 3.8% surtax on investment income, layered on top of your regular capital-gains and dividend tax, and it lands on exactly the kind of household this site is written for. The frustrating part is the threshold. It was set in 2013 and it has never moved since, so every year of inflation drags more retirees over the line.

What actually triggers it

The NIIT applies when your modified adjusted gross income clears a fixed threshold: $250,000 for a married couple, $200,000 for a single filer. Above that line, you pay 3.8% on the smaller of your net investment income or the amount of MAGI over the threshold. Net investment income is the usual suspects: interest, dividends, capital gains, rents, royalties, and passive business income. It is not IRA or 401(k) withdrawals, RMDs, Social Security, or pension income.

That last point is the lever, and it’s a strange one. A traditional IRA withdrawal isn’t itself subject to the NIIT, but it raises your MAGI, which can drag your investment income over the threshold and into the surtax. So the tax-deferred account you thought was unrelated to investment tax is quietly the thing pushing your dividends into the 3.8% zone. The triggers and the tax base aren’t the same pool, and that mismatch is where the planning lives.

The threshold that never moves

Here’s the structural problem worth naming. The regular tax brackets, the standard deduction, the capital-gains breakpoints, and the IRMAA Medicare tiers all rise with inflation each year. The NIIT thresholds do not. They’ve been frozen at $250,000 and $200,000 for over a decade. The math is unforgiving. A couple who was comfortably under the line in 2013 may now clear it on dividends alone, not because they got richer in real terms but because the line stood still while prices doubled. This is bracket creep by design, and it means the NIIT catches a wider net of retirees every single year.

How you actually manage it

You can’t repeal the surtax, but you can manage the MAGI that triggers it. The moves are familiar from the rest of tax planning. Time your capital gains so you don’t bunch a large realization into a year that also has high other income. Use tax-loss harvesting to net investment income down, since the NIIT applies to net gains. Favor tax-exempt municipal bond interest, which doesn’t count as net investment income and doesn’t lift MAGI. And sequence Roth conversions carefully, because while the conversion itself isn’t investment income, it raises MAGI and can pull your dividends and gains into the surtax in that year.

Picture a couple with $230,000 of MAGI, of which $60,000 is dividends and gains. They’re under the line, no NIIT. They convert $40,000 to a Roth. MAGI is now $270,000. The conversion isn’t taxed by the NIIT, but it pushed them $20,000 over the threshold, so they now owe 3.8% on $20,000 of their investment income. The conversion was probably still worth it, but the surtax is a hidden line item they should have seen coming.

If your accounts are large

For households with $3M or more, the NIIT is rarely avoidable outright, so the goal shifts to controlling when you pay it. Concentrate large gains into years you’ve already cleared the threshold by a wide margin, since the surtax caps at the lesser of your investment income or your excess MAGI. Push tax-inefficient, income-throwing assets into your IRA where their yield doesn’t feed the surtax, and keep municipal bonds and growth equities in the taxable account. This is asset location doing double duty. And the same step-up logic applies. Holding appreciated assets until death erases both the capital-gains tax and the NIIT on the gain.

The NIIT is a small rate on a frozen threshold, which makes it a tax that grows on autopilot. You beat it by managing MAGI, not by ignoring it. For the surtax in the context of your other income levers, see NIIT planning for retirees.