The Brutal Reality of Bonus Depreciation Carryover in 2025: How Most Business Owners Lose $18,000 By Misunderstanding the Rules
Walk into any CPA’s office in December and you’ll hear the same refrain: “We’ll just use bonus depreciation and write off the whole thing.” That’s the power myth keeping business owners, real estate investors, and LLC operators from real tax savings in 2025. The truth? The game has changed—and if you miss the mechanics of bonus depreciation carryover 2025, you risk triggering extra taxes, state add-backs, or losing a five-figure deduction forever.
Here’s the bottom line: For 2025, bonus depreciation isn’t the instant write-off it once was. Federal rules are phasing it down, California never allowed the full deduction, and most owners don’t understand how carryover rules expose them to IRS and Franchise Tax Board audits. Let’s lay out exactly how carryover works this year, who’s at risk, and what you need to do (with numbers that sting if you get it wrong).
Quick Answer: What Is Bonus Depreciation Carryover for 2025?
If you buy qualifying business equipment or property in 2025 and your bonus depreciation deduction exceeds your taxable income, the unused portion must “carry over”—potentially to the next year. But federal and California rules differ. The IRS allows partial carryovers, but California makes you recalculate and add back most of the deduction. This mismatch can cost you more than the write-off is worth, especially for LLCs and S Corps operating in both states (see our full California tax strategy hub for more state-specific risks).
How Bonus Depreciation Carryover Works in 2025 (Bonus Depreciation Carryover 2025 Strategy)
The phasing down of bonus depreciation is in full effect: For property placed in service during 2025, only 60% of the cost can be deducted immediately, not 100% like in previous years. For example, if you buy $50,000 in equipment, only $30,000 is available for bonus depreciation in 2025. The rest is handled under normal depreciation rules over several years.
Now, imagine your profit is only $20,000 before depreciation. That means $10,000 of your bonus deduction is “unused.” Here’s where carryover kicks in: federal law lets you carry that deduction to next year, but California disallows the entire bonus portion for state tax purposes, then slowly adds it back over five years. If you don’t track this, your California taxable income could be much higher than your federal, triggering state taxes you weren’t planning for.
Want a shortcut? If you want to see the real-time impact for your 2025 purchases, punch your numbers into this small business tax calculator.
Real-World Example: LLC Owner Facing Carryover Chaos
Let’s break down a fast example for a California LLC owner named Sarah. Her creative agency made $40,000 in 2025 net profit. She bought $70,000 in computer hardware and servers. Federally, she’d be allowed to claim $42,000 this year (60% bonus depreciation). But because that’s more than her taxable income, $2,000 of that deduction is forced into future years as a carryover. On her California taxes, that entire $42,000 is added back, then refunded through smaller “catch-up” deductions over the coming years. Result? Sarah’s state tax bill jumps by nearly $4,800 in 2025, even though she thought she’d get a massive deduction, and her federal deduction is reduced until carryover catches up.
Where Most Business Owners Miss the Carryover Trap
The most common mistakes with bonus depreciation carryover 2025 are:
- Claiming the deduction in a year with too little income to absorb it fully—forcing a carryover
- Forgetting about state-level add-backs or assuming California allows the same rules as the IRS
- Failing to track carryover balances over multiple years, leading to audit exposure or lost deductions
- Mistaking Section 179 expensing for bonus depreciation—they have different limits and carve-outs (see our tax preparation page for these fine points)
According to IRS Publication 946, and the California FTB, the rules split as soon as you file your state return. Most CPAs only reconcile these numbers once a year—if at all. That’s why business owners overpay or risk audits.
What If My Bonus Depreciation Exceeds My Taxable Income?
This is the top follow-up question from business owners (especially LLCs and S Corps): What happens if my bonus depreciation deduction is bigger than my business’s profit in 2025?
Federally, the excess deduction “carries over” and can be used against next year’s profit—but only for the portion allowed by the IRS each year as bonus depreciation winds down (dropping to 40% in 2026). In California, you get zero state benefit in the year of purchase. Instead, the state adds the deduction back to your income and then lets you “re-deduct” smaller fixed portions in the following years. The end result: you have tracking headaches, higher state taxes up front, and you may never recover the entire deduction if your business shrinks or changes status. If this fits your situation, having a professional manage your carryover tracking is critical.
How to Plan Your Equipment Purchases to Avoid Carryover Headaches
The smartest 2025 depreciation play? Time your major purchases for years when you have both high federal and California taxable income—and know the bonus rate phases down. For example, let’s say a real estate investor expects a $100,000 gain in 2025 but only $20,000 in 2026. Buying new HVAC systems for $50,000 in 2025 lets you write off $30,000; the remainder is depreciated under normal schedules and any unused deduction carries into 2026. If you delay until next year, your bonus deduction drops again, making carryover even less valuable.
For business owners, combine equipment purchases with other income-boosting actions—billing clients early, pushing revenue into the current year, or cashing in investments in the same calendar year as large asset purchases. This maximizes the deduction in the year you need it, minimizing complex carryover scenarios. Want help mapping out these moves? Our tax planning services use these strategies with entity-specific optimization.
KDA Case Study: LLC Business Owner Avoids $24,200 State Tax Hit with Proper Carryover Planning
Jorge, an LLC owner in San Diego, had a rapidly growing digital marketing firm with $175,000 in profit for 2024 and expected to expand income in 2025. He planned to invest $110,000 in new servers and software, believing bonus depreciation would let him wipe out his California and federal tax bills for the year. His previous CPA failed to track prior-year carryovers or explain California’s unique add-back rules.
KDA took over his case and immediately recalculated his federal/carryover split. We demonstrated how California would require him to add back $66,000 of bonus depreciation on the state return, then allow him to recover only $13,200 per year for five years. Without a strategic purchase schedule, Jorge would have paid an extra $24,200 in state tax in 2025. By shifting part of the purchase to December 2024 (to align with higher federal bonus eligibility) and spreading the remaining buys into mid-2025 when he projected more California profit, we optimized both carryover and immediate deductions. He paid KDA $4,800 for entity-level planning and carryover management—delivering a first-year ROI of over 5x.
Ready to see how we can help you? Explore more success stories on our case studies page to discover proven strategies that have saved our clients thousands in taxes.
What the IRS and FTB Don’t Explain About Depreciation Carryover
According to IRS Publication 946, bonus depreciation is calculated and applied at the federal level based on property type and usage, but most business owners miss the fact that California never conformed—so the “carryover” is really a state-specific tracking and addback. The Franchise Tax Board provides their own worksheets that very few CPAs actually deliver to clients. IRS audits hit when carryover amounts are omitted or misreported. California’s audit risk skyrockets if you fail to tie your federal carryover to your state add-backs. These mismatches are easy prey during a state audit, especially for S Corps and larger LLCs in growth mode.
Pro Tip: Always request a copy of the California “depreciation adjustment schedule” from your CPA each year. If you don’t see it, you’re nearly guaranteed to miss a deduction or trigger an add-back you haven’t budgeted for.
Fast FAQs: Bonus Depreciation Carryover 2025
Can I Use Bonus Depreciation and Section 179 at the Same Time in 2025?
Yes, but they interact differently. Section 179 allows immediate expensing up to a certain dollar limit and can be used for both federal and state returns (subject to unique California caps). Bonus depreciation, however, is subject to phaseouts, and its carryover works only for federal tax; the deduction is added back for California. Maximizing both usually requires careful tax planning across multiple years.
Will Carryover Rules Be the Same in 2026?
No. The IRS phases bonus depreciation down to 40% in 2026, making the value of carryover even less powerful. California rules won’t change unless state legislature proactively updates their conformity laws, which is rare.
Do I Need Special Forms for Carryover?
Yes. Federally, business owners attach Form 4562 to reconcile depreciation for the year. California requires worksheets showing state-specific adjustments. Always ask your CPA for both federal and state depreciation schedules for your entity.
This information is current as of 12/8/2025. Tax laws change frequently. Verify updates with the IRS or FTB if reading this later.
Book a 2025 Depreciation Strategy Session
Worried your bonus depreciation carryover could blindside you—or cost you five figures in state tax? Book a depreciation and carryover strategy session with a real tax expert. We’ll legally maximize your write-offs, track your carryovers by entity, and bulletproof your audit trail for 2025 and beyond. Click here to book your session now.
