Tax Loss Harvesting vs Roth Conversion: Which to Do First in 2026
Two tax moves compete for the same December to-do list: selling losers in your brokerage account, and converting traditional IRA dollars to Roth. The question behind tax loss harvesting vs Roth conversion is which one deserves your first dollar of attention, and the answer depends on one number most guides skip: your taxable income after the standard deduction. This guide gives you the 2026 bracket math, the $3,000 trap that surprises people who assume losses can wipe out a conversion, and a simple order of operations.
The Two Moves in Plain English
Tax-loss harvesting means selling an investment in a taxable brokerage account for less than you paid, then using that realized loss to offset taxable gains. According to the IRS (Topic No. 409), capital losses first offset capital gains, and if losses exceed gains you can deduct up to $3,000 per year against other income ($1,500 if married filing separately), carrying the remainder forward to future years. The catch is the wash sale rule: IRS Publication 550 disallows the loss if you buy a substantially identical security within 30 days before or after the sale. We walked through how that rule shrank one reader-style deduction from $3,100 to $403 in our wash sale rule case study.
A Roth conversion moves money from a traditional IRA (or pre-tax 401(k) rollover) into a Roth IRA. The converted amount is added to your ordinary income for the year and taxed at your marginal rate. In exchange, future growth and qualified withdrawals are tax-free. Since the 2017 tax law, the IRS no longer allows you to undo a conversion after the fact, so the tax bill you create is the tax bill you keep.
Both moves lean on the same lever: you are choosing which year to recognize income or losses. That is why people confuse them, and why the order matters.
Tax Loss Harvesting vs Roth Conversion: Side-by-Side Comparison
| Factor | Tax-Loss Harvesting | Roth Conversion |
|---|---|---|
| Account type | Taxable brokerage only | Traditional IRA / pre-tax rollover to Roth IRA |
| What you get | Lower tax now; offsets gains plus up to $3,000 of ordinary income | Tax-free growth and withdrawals later |
| Tax cost today | None (it reduces tax) | Ordinary income tax on the full converted amount |
| Is it permanent? | No, lowers your cost basis, so it mostly defers tax | Yes, taxes paid now are final |
| Deadline | Trade must settle by Dec 31 | Must be completed by Dec 31 |
| Needs a down market? | Yes, requires a position with a loss | No, works in any market (cheaper after drops) |
| Main trap | Wash sale rule | Pro-rata rule and bracket creep |
The Trap: Harvested Losses Can’t Erase a Roth Conversion
Here is the misunderstanding that sends people to the wrong order of operations. A Roth conversion creates ordinary income. Capital losses are applied first against capital gains, and only $3,000 per year can offset ordinary income. So if you harvest $25,000 of losses and have no gains, only $3,000 reduces this year’s conversion income; the other $22,000 carries forward. Losses do not “cancel” a conversion dollar for dollar.
A quick hypothetical (illustrative numbers, not advice): a single filer has $45,000 of taxable income and converts $20,000. Under 2026 brackets (per the Tax Foundation’s summary of IRS figures), the 12% bracket ends at $50,400 for single filers, so $5,400 of the conversion is taxed at 12% ($648) and $14,600 at 22% ($3,212), for $3,860 total. Now add a $3,000 harvested loss deduction. It lowers income at the top of the stack, where the rate is 22%, so it saves $660. Useful, but it covers only about 17% of that conversion tax bill.
When Harvesting Losses Should Come First
Harvest first when you have realized capital gains this year, from a fund distribution, a rebalance, or a sale. Gains are where losses do their heaviest lifting, since they offset dollar for dollar with no $3,000 cap. If you are in the 15% long-term gains bracket, every $1,000 of gain you absorb saves $150 in federal tax (plus the 3.8% net investment income tax for higher earners).
Harvest first, too, if your conversion room is small. If you are near the top of the 12% bracket, a few thousand dollars of conversion is all you can do efficiently anyway, and the loss strategy has a lot more room to work. Our deep dive on whether tax-loss harvesting is worth it for small portfolios gives a quick formula for deciding if the savings beat the hassle, and our comparison of tax gain harvesting vs tax loss harvesting covers the flip side when your income is unusually low.
One honest caveat: harvesting lowers your basis. You swap a position for a similar one, and your future gain gets larger by the amount of the loss. The benefit is deferral, and deferral is only worth something if you can reinvest the savings or eventually realize gains at a lower rate.
When a Roth Conversion Should Come First
Convert first when your income this year is unusually low, such as a gap year between jobs, early retirement before Social Security, or a big business-expense year. The 2026 standard deduction is $16,100 for single filers and $32,200 for married couples filing jointly, so you can fill the 10% and 12% brackets cheaply. For married couples, the 12% bracket runs up to $100,800 of taxable income.
The stacking order matters too. Ordinary income, including your conversion, sits below long-term gains. The 0% long-term gains rate applies up to $49,450 of taxable income for single filers and $98,900 for joint filers. A conversion can push gains that would have been tax-free into the 15% bracket. That is a hidden cost, and it is exactly the situation where harvesting some losses against those gains first can protect your 0% space.
If you are early-retirement minded, our piece on the Roth conversion ladder explains why conversions are a core tool before age 59½. And if your IRA holds a mix of pre-tax and after-tax dollars, remember the pro-rata rule on IRS Form 8606: you cannot choose to convert only the after-tax dollars. The backdoor Roth IRA guide shows how that rule bites.
My Own Process (and the Honest Result)
I’m a software engineer by trade, and I approach my own finances the way I’d approach a system with two competing jobs: write down the inputs, then decide the order. I run my own index-fund portfolio in tax-advantaged and taxable accounts without an advisor, partly out of curiosity about behavioral economics and partly because I like building small automations around the paperwork. When I first compared these two strategies, I assumed harvested losses could “pay for” my conversion. They can’t, at least not beyond the $3,000 limit, and that was a useful correction. What changed my order of operations was building a simple spreadsheet that estimates taxable income before I touch either move. The honest answer: the spreadsheet mattered more than the strategy.
A Practical Order of Operations
- Estimate your taxable income for the year. Take projected income, subtract the standard deduction (or itemized total), and note where you sit in the brackets.
- List realized gains. Fund distributions and any sales count. Gains are the best home for harvested losses.
- Harvest losses to cancel gains first. Then decide whether to use the $3,000 ordinary-income allowance.
- Re-estimate taxable income. See how much room is left in your current bracket.
- Convert up to the top of a bracket you’re happy with. Watch the 0% gains threshold, IRMAA surcharges if you’re near Medicare age, and ACA subsidy cliffs if you buy coverage on the exchange.
- Pay the tax from outside the IRA. Paying conversion tax out of the converted money shrinks the Roth benefit. Our guide to asset location helps decide which accounts should hold what.
Both moves have to wrap by December 31, so run this checklist in October or November, not on December 30th.
Tax Loss Harvesting vs Roth Conversion: Which Should You Choose?
| Your situation | Do first |
|---|---|
| Realized gains this year, high bracket | Harvest losses |
| Low-income year, room left in 10-12% bracket | Roth conversion |
| No taxable account or no unrealized losses | Roth conversion (harvesting isn’t available) |
| Gains currently in the 0% bracket | Check that the conversion won’t push them into 15% |
| Large pre-tax IRA balance plus after-tax basis | Model the pro-rata rule before converting |
Frequently Asked Questions
Can capital losses offset a Roth conversion?
Only partly. Losses first offset capital gains, then up to $3,000 of ordinary income per year, which includes conversion income. Anything beyond that carries forward.
Does a Roth conversion trigger a wash sale?
No, a conversion itself is not a sale of the security. But if you sell at a loss in your brokerage account and buy a substantially identical fund in your IRA within 30 days, the IRS can treat that as a wash sale, so avoid repurchasing in the Roth.
Is tax loss harvesting worth it in a low bracket?
Sometimes not. If your long-term gains rate is 0%, absorbing gains saves nothing, and harvesting just lowers basis. The $3,000 ordinary-income deduction still helps.
When is the deadline for each strategy?
Both must be completed by December 31 of the tax year. Unlike IRA contributions, you can’t do a Roth conversion for 2026 in April 2027.
Which saves more over the long run?
They solve different problems. Harvesting defers tax; a conversion pays tax now to remove it later. If your future rate will be higher than your current rate, conversion tends to win; if it will be lower, deferral can be better. Run your own numbers or talk to a CPA, since this is general education, not tax advice.
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