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Enter your situation once and six calculators re-run together, each showing its math line by line with the statute behind every line. They write the verdict in plain English with the dates that follow from it, rank the thresholds you are nearest, and print dated. Nothing you type is sent anywhere: the arithmetic runs in this page and the figures stay in it. Estimates on the published 2026 IRS, SSA and BLS figures, not tax advice, but real arithmetic you can check.
Your numbers
The salary card's midpoint feeds the breakeven card, the breakeven verdict feeds the entity comparison, and the quarterly and overpayment cards read the entity you actually have. Drag a slider and watch all six move.
In plain English
Written from the ledgers below, sentence by sentence, with nothing added. An estimate, not tax advice.
What to do now
Thresholds ahead
Scenario compare
| Result | Pinned | Now | Change |
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If you run an S-corp, or are thinking about one
Three calculators that walk an owner from "is the election right for me" to "what salary clears the IRS reasonable-comp test." Built on the published 2026 IRS thresholds and the BLS May 2025 wage tables, with the arithmetic shown line by line.
Sole prop, S-corp, partnership, or C-corp. Total federal tax and cost at your profit, with the section 199A wage limit, guaranteed payments, and the net investment income tax modeled, so the right structure is obvious, not assumed.
Texas-resident assumed (no state income tax). Non-SSTB QBI; the UBIA alternative is not modeled. An estimate, not tax advice.
At the salary in your profile, or the BLS midpoint if you left it blank, does the S-election clear the extra compliance cost. The curve shows where it starts to.
Reads the salary from your profile and the midpoint from card 03. An estimate, not tax advice.
The actual BLS wage percentiles for your role and metro, a percentile you can justify, and documentation language for the workpaper.
BLS OEWS May 2025 annual wages, cross-industry. Refreshed each spring. An estimate, not tax advice.
Planning tools for the general case
Quarterly estimated tax with the safe harbor and the annualized method, an R&D credit estimator with the payroll-tax offset and the Texas franchise credit, and an overpayment benchmark that surfaces planning positions worth exploring.
What the IRS requires by each due date for the entity in your profile, what you have paid, and what to send now, including any catch-up.
Through the end of this period. Leave at $0 to assume an even year.
Section 6654: 90 percent of this year or the prior-year safe harbor, whichever is lower. An estimate, not tax advice.
Built for SaaS and product companies in their first years of research spend. The federal credit, what a young company can take against payroll tax, and the Texas franchise credit.
Leave at $0 for a first-year company; the 6 percent startup rate applies.
Alternative simplified credit under section 41(c)(4). An estimate, not tax advice.
Reads your entity and profit from the profile. Surfaces the planning positions worth exploring, each priced at your own brackets, not a flat rate.
0 positions found. Each is estimated on its own; they interact on a real return. An estimate, not tax advice.
These calculators use the published 2026 IRS thresholds (Rev. Proc. 2025-32), the 2026 Social Security wage base from SSA, the 2026 retirement plan limits (Notice 2025-67), the Internal Revenue Code and Texas Tax Code as amended in 2025, and BLS May 2025 OEWS wage data. They are for planning illustration only and not a substitute for a prepared return or personalized tax advice. Real numbers depend on the full picture, which is what the first call is for.
Every figure above comes from one constants block, refreshed Sep 3, 2026, checked against hand-computed cases each time it changes. The sources, so you can check them too.
| What | Value | Source | Refreshed |
|---|---|---|---|
| Income tax brackets, standard deduction, QBI thresholds, qualified-dividend breakpoints | Rev. Proc. 2025-32 | IRS, Oct 9, 2025, tax year 2026 inflation adjustments after Pub. L. 119-21 | Each October for the next tax year |
| Social Security wage base | $184,500 | SSA 2026 Fact Sheet, Oct 24, 2025 | Each October |
| Solo 401(k) deferral and total limits | $24,500 and $72,000 | IRS Notice 2025-67 | Each November |
| Self-employment tax | 15.3% on 92.35% of net earnings | IRC sections 1401 and 1402(a)(12); Additional Medicare Tax 0.9% under section 3101(b)(2) at statutory thresholds not indexed | Statutory |
| Net investment income tax | 3.8% above $200,000 / $250,000 | IRC section 1411, thresholds not indexed | Statutory |
| C-corporation rate | 21% | IRC section 11(b), made permanent by Pub. L. 115-97 | Statutory |
| Qualified business income deduction | 20%, W-2 wage limit 50% | IRC section 199A; phase-in window widened to $75,000 / $150,000 by Pub. L. 119-21; specified service trades (health, law, accounting, financial services, brokerage) under section 199A(d)(2) and Reg. 1.199A-5 phase to zero across the window | Thresholds each October |
| S election deadline | March 15 for a calendar year | IRC section 1362(b), Form 2553 by the 15th day of the third month; late election relief within 3 years and 75 days under Rev. Proc. 2013-30 | Statutory |
| Estimated tax | 90% current or 100% / 110% prior | IRC section 6654(d); annualized installment method section 6654(d)(2); $1,000 floor and the zero-prior-year rule section 6654(e); due dates Form 1040-ES | Statutory; dates each January |
| Underpayment charge | 7% a year, simple | IRC section 6621(a)(2), the federal short-term rate plus 3 points, set quarterly by revenue ruling; the rate in effect when this page was refreshed | Each quarter |
| Research credit | ASC 14%, startup 6%, contractors 65% | IRC section 41(c)(4), 41(b)(3); payroll-tax offset up to $500,000 for a qualified small business, section 41(h); reduced credit election section 280C(c)(2); domestic research expensing section 174A (Pub. L. 119-21) | Statutory |
| Texas franchise tax research credit | 8.722%, startup 4.361% | Tex. Tax Code sections 171.651 to 171.665 as amended by SB 2206 (89th Leg., 2025), effective Jan 1, 2026; limited to 50% of franchise tax due, 20-year carryforward | Legislative sessions; verify with a Texas CPA |
| Home office and the Augusta rule | $5 per sq ft to 300 sq ft; 14 rental days | IRC section 280A(c) and Rev. Proc. 2013-13 (simplified method); section 280A(g) | Statutory |
| Wage percentiles | BLS OEWS May 2025 | Occupational Employment and Wage Statistics, annual wages, cross-industry, DFW, Austin, Houston, San Antonio, El Paso, national; baked by scripts/cowell-oews-bake.py | Each spring when the new May release publishes |
103 assertions across 21 hand-computed cases, re-run on every change to the engine and last run Sep 4, 2026. The derivations are written into the test file, so the annual refresh can redo them rather than trust them.
Questions I am answering this week
A running sample of what people actually ask. Each card opens a full written answer, the way I would explain it on a first call.
Start now. An S-election in effect means the IRS expects payroll-based salary across the whole year, not a December catch-up check.
Read the full answerUsually routine. A CP2000 is an automated mismatch notice, not an audit. Often the IRS is simply missing your cost basis and you owe nothing.
Read the full answerPossibly, and the timing is tight. If the average guest stay is seven days or less and you materially participate, the loss can reach your W-2 income.
Read the full answerAlmost certainly yes. Engineering wages, contractor costs, and cloud spend typically qualify, and a pre-profit company can take the credit as cash back.
Read the full answerYes. You can generally amend within three years, and a missed QBI deduction is worth up to 20 percent of qualified business income.
Read the full answerA November wedding makes you married for all of 2026. Joint wins for most couples, but medical bills or student loans can flip it.
Read the full answerTwo things before April. Reconstruct every transaction cost basis and holding period, and check whether the gain triggers an estimated payment.
Read the full answerUnusually clean on the personal side, since both states have no income tax. The real question is whether your LLC creates a nexus obligation in Tennessee.
Read the full answerFrom estimate to plan
If one of these tools surfaced a number that surprised you, that is exactly what the first call is for.
