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What can you still do before December 31?
Most tax decisions that change your bill have to be made before year-end — not in April. Enter your 2026 numbers and see the exact dollar value of each move still available: retirement contributions, equipment purchases, California PTET, and deductions you might be leaving unclaimed.
2026 estimates · Not tax advice
Section 179 / bonus depreciation — 0 if nothing planned
Total tax savings available before Dec 31
$10,340
At your 22% federal marginal rate · 2026 estimates
Retirement plan
Room available$10,340
You have $47,000 of remaining contribution room in your Solo 401(k). Contribute before Dec 31 to claim the deduction this year. If you don’t have a plan yet, it must be established by December 31.
Equipment & software (§179)
$2,200 per $10k$2,200 per $10k
Section 179 lets you deduct 100% of qualifying business equipment and software in the year of purchase. Must be placed in service by December 31. Enter a planned amount above to see your exact savings.
Computers, monitors, phones, office furniture, machinery, vehicles (limits apply), software.
Accountable plan & deductions
Review this$1,000–$5,000+
An accountable plan lets your S-corp reimburse you tax-free for home office, business vehicle use, phone, and travel. Without a written plan, these expenses can’t be run through the corporation. This can’t be calculated here — it depends on your actual usage — but it’s typically $1,000–$5,000+ per year for most owners.
How accountable plans work →2026 IRS limits (IRS Notice 2025-67 / Rev. Proc. 2025-32 / OBBBA). Solo 401(k): $24,500 employee deferral + $8,000 catch-up (age 50+); employer contribution 25% of W-2 (S-corp) or 20% of net SE income (sole prop); total cap $72,000 / $80,000. SEP-IRA max $72,000. Section 179 limit $2,560,000; 100% bonus depreciation permanent per OBBBA (Pub. L. 119-21). California PTET benefit estimated at 9.3% effective CA rate — actual depends on income bracket. Marginal rate computed from projected income using standard deduction only. Sole prop equipment savings include approximate SE tax benefit (~7%). Accountable plan estimates are illustrative only. Not tax advice — consult a CPA before acting.
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Tax data sources
- IRC §179 — Section 179 expensing for business equipment
- IRC §168(k) — Bonus depreciation
- IRC §401(k) — Qualified cash or deferred arrangements
- Rev. Proc. 2024-40 — 2025 income tax inflation adjustments (brackets, standard deduction, capital gains thresholds)
- IRS Notice 2024-80 — 2025 retirement plan contribution limits