$114,000 Less Ceiling and Nobody Mentioned It

Congress handed you a big write-off. Then they shrank the bag you carry it in.

The One Big Beautiful Bill made bonus depreciation permanent. 100%. Buy a building. Run a cost segregation study. Deduct the whole thing, day one. That was the headline. Everybody clapped.

Here is the line nobody read.

The same bill made the excess business loss cap permanent. Section 461(l). It limits how much business loss you can use in a single year. For a married couple filing jointly, the cap in 2025 is $626,000. In 2026, it drops to $512,000.

Not because Congress wrote a new limit. Because they swapped one number in the statute. "2024" replaced "2017" as the base year for inflation adjustments.

BDO put it this way:

Right. Eight years of inflation. Gone. One line of code. That is $114,000 less you can write off this year.

Now put the two pieces together. The bill says: take the big write-off. Also: we lowered the ceiling on how much you can use.

The accounting firm Moss Adams ran the math. A married couple buys a multifamily building. Cost segregation plus bonus depreciation generates a $1 million loss on paper. They also sold stock that year for a $1 million gain.

You would think the loss covers your tax bill. It does not.

The 461(l) cap kicks in. They can only use $626,000 of that loss. The other $374,000? Trapped. It converts into a net operating loss and rolls forward.

And next year, the cap is even lower.

That $374,000 rolls forward as an NOL. But NOLs have their own rule. Section 172 says you can only use an NOL to offset 80% of future taxable income. Not 100%.

You lost a dollar. You get eighty cents back. Spread over future years. The IRS keeps the float.

Two cuts from one bill. The bigger the write-off you chase, the more lands in the box. The box locks. The box pays back at eighty cents.

Look, this is not an accident. It is budget math.

When Congress passes a tax cut, it needs a "pay-for." Something that raises revenue on paper so the bill scores under reconciliation rules. The Joint Committee on Taxation scored 461(l) at $149.7 billion over ten years. The S Corporation Association estimates the real impact was closer to $7 or $8 billion.

I mean. Off by a factor of twenty. But it scored. And that score funded the headline: "permanent bonus depreciation."

The depreciation is the bait. The lowered cap is the hook.

So what do you do.

Look, you do not have to take the full write-off. You can elect out of bonus depreciation by asset class. If the whole deduction pushes you past the 461(l) cap, spread it across years. Stay under the ceiling. Take less candy now so none of it gets locked in the box.

Then there is timing. Section 1231 gain from selling business property counts as business income on Form 461. That means a 1231 gain in a big loss year raises the ceiling on what you can deduct. I mean, the cap is not one number for everybody. It moves. Coordinate your asset sales with your loss years and the cap moves with you.

The Roth conversion is trickier. Do it the year after the big loss. Not the same year. Here is why. The trapped loss becomes an NOL. Next year, that NOL can offset Roth conversion income, subject to the 80% haircut. Eighty percent of something beats zero.

But if you convert in the same year you blow past the cap? The Roth income does not count as business income. It sits on the wrong side of the line. It cannot raise your 461(l) ceiling. It just sits there, taxed in full, while your business loss gets trapped anyway. Two bills. No offset.

Congress handed you the write-off with one hand. They shrank the bag with the other. The fine print funded the headline.

Sure.