What Is Self-Employment Tax? (And Why Is It So High?)
15.3% on your net profit, on top of income tax. Why you pay both halves, how the deduction works, and when the S-corp math starts making sense.
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Tax and planning questions answered by a CPA — with the math shown. Business-owner focused. No email required, no sign-up, no generic fluff.
Quick answers
For the moments when you need a straight answer, not a consultation. No gates, no forms.
15.3% on your net profit, on top of income tax. Why you pay both halves, how the deduction works, and when the S-corp math starts making sense.
ReadA 1099 is a report, not a bill. What the different types mean, what to do when the amount is wrong, and why you owe tax even without a form.
ReadThe penalty is smaller than you think. The actual math, how to catch up, and the two habits that eliminate this problem permanently.
ReadMost notices are automated and fixable. What each common notice type means, what requires action, and the one thing you should never do.
ReadA filing extension is free and automatic. The filing penalty (5%/month) is ten times the payment penalty — always file, even if you can't pay.
ReadAn LLC is a liability tool, not a tax tool. When it matters, when it doesn't, and the California $800/year detail most people find out too late.
ReadOnly the business portion. Standard mileage vs. actual expenses, why your commute doesn't count, and what the IRS mileage log actually needs.
ReadThe 3-year rule, what counts as documentation, and the simplest digital system that keeps you clean without a shoebox of receipts.
ReadSection 199A lets most pass-through owners deduct 20% of business income. Who qualifies, what kills it for service businesses, and what it means for your S-corp salary.
ReadRegular and exclusive use — that's the whole rule. Two methods for calculating it, what renters vs. homeowners get, and why S-corp owners have to do it differently.
ReadYour share of income from a partnership, S-corp, or trust. It arrives late, you owe tax even if no cash came out, and yes — you need to wait for it before filing.
ReadSalary through payroll, distributions from the business account — two types, two tax treatments. How to set them up and what the IRS actually requires.
ReadThe basics
Plain-English explainers for new owners who want to understand what they’re looking at.
Sample P&Ls for a personal trainer, therapist, salon, and franchise restaurant — plus what gross margin, net margin, and cash flow actually mean.
ReadThe most common expense categories with QuickBooks and Xero names, plus the special rules for auto, meals, and home office.
ReadThe master list of every category your business money gets sorted into — with sample charts for a service business and a product-based business.
ReadWhat an EIN is, why every owner needs one even without employees, and how to apply directly from the IRS without paying anyone.
ReadWhen you have to collect it, what nexus means, California rates and registration, how to remit, and the four mistakes that create liability.
ReadWeek-by-week action plan: EIN, business bank account, tax savings habit, bookkeeping software, insurance quote, and the CPA conversation you shouldn't skip.
ReadOwnership percentages, profit allocation, management authority, and buyout provisions — the document that protects both partners, especially when contributions aren't equal.
ReadWave, QuickBooks, Xero, and FreshBooks compared — who each one is for, what it costs, and the QuickBooks Self-Employed trap to avoid.
ReadIt doesn't go on Schedule C — it goes on Schedule 1 and reduces your AGI. Who qualifies, what's deductible, and the required extra step for S-corp owners.
ReadI-9, new hire reporting, workers comp, EDD registration, payroll service setup — the step-by-step guide to the legal and tax obligations most owners skip.
ReadForm 2553, the March 15 deadline, late election relief, and what to set up in the first 30 days once the election goes through.
ReadThe IRS requires a market-rate salary before you take distributions. How auditors evaluate S-corp compensation, what a defensible salary looks like, and the QBI deduction interaction.
ReadAn LLC is a legal structure; an S-corp is a tax election — most S-corp owners have both. When the election pays off, when it doesn't, and what the compliance costs actually are.
ReadMost profitable small businesses default to S-corp. But a C-corp's flat 21% rate makes sense for VC-backed startups, businesses retaining large profits, and founders building toward a Section 1202 QSBS exit (up to $10M in gain exclusion).
ReadMost owners are over-insured on the visible risks and under-insured on the invisible ones. A framework for thinking about business and personal coverage — and the five gaps that show up most often.
ReadGeneral liability, professional liability, workers comp, cyber, commercial auto, key-person — what each type covers, when it matters, and the gap most service businesses don't realize they have.
ReadHealth, term life, disability, personal umbrella — which coverages are non-negotiable for self-employed owners, the disability gap nobody talks about, and why whole life is over-sold.
ReadS-corp health on the W-2, HSA strategy, disability premium-vs-benefit taxability, buy-sell life insurance and the operating agreement. Why these decisions go wrong when the broker, CPA, and advisor never speak.
ReadPlanning ahead, not just filing
S-corp salary, quarterly estimates, and return coordination — the three levers that matter most for a profitable service business, with embedded calculators.
“My business is making money, but tax planning feels reactive.”
Filing a return tells you what already happened. Planning changes what the next one looks like. Here's what the difference looks like in practice.
ReadWhen business and personal returns are handled separately, key decisions get made in the dark: retirement limits, QBI, distribution timing.
ReadMost owners have a CPA and an advisor who have never spoken. Here's what gets missed when those two conversations stay separate.
ReadSix tax reduction strategies used by high-income business owners and investors, from entity structure and retirement plans to charitable giving and timing.
ReadSole props and S-corps can deduct up to 20% of pass-through profit on their personal return. Income thresholds, SSTB restrictions, and how salary calibration affects the deduction.
ReadThe AB 150 election lets California pass-through entities pay state income tax at the entity level — making it federally deductible without the SALT cap ($40,400 for 2026, phases down above $505k). June 15 deadline. Most profitable California S-corps should be doing this.
ReadSE tax is 15.3% on every dollar of net profit — on top of income tax. How it's calculated, what the deductible half saves, and why the S-corp election is the primary way to reduce it.
ReadGoing from W-2 to 1099 changes your tax picture significantly — SE tax applies to every dollar, no withholding, quarterly payments required. What the full bill looks like and the three moves that reduce it.
ReadA Solo 401(k) caps at $70,000. A cash balance plan lets a profitable owner in their 50s deduct $275,000–$350,000+ per year. How the contribution is calculated, who it works for, and the December 31 setup deadline.
ReadS-corp shareholders, partners, and trust beneficiaries all receive K-1s. Each box flows to a different line on your personal return. What the key boxes mean, the passive activity rules that limit losses, and why K-1s delay personal returns.
ReadThe 3.8% NIIT applies to investment income above $200,000 MAGI (single) / $250,000 (MFJ). It applies to capital gains, dividends, passive business income, rental income, and gains from selling a business — on top of regular rates.
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Getting money out of the business
How much to take out, when, in what form, and where it goes — with distribution planning, tax impact scenarios, and the questions your CPA and advisor should be answering together.
“Cash is building up in the business, but I don't have a personal wealth plan.”
Owner draws, payroll, distributions, and S-corp reasonable compensation: how the method depends on entity type and why sloppy owner pay creates audit risk.
ReadWhen the annual LLC tax applies, when it can be deducted, and whether your entity structure still makes sense.
ReadYes, and not every transaction is an expense. How to categorize correctly so your books actually tell you something useful.
ReadHow CDTFA-230 resale certificates work, when to use one, and the real consequences of misuse.
ReadWhen you buy things to resell, you're taxed on margin, not revenue. Cost of goods sold, resale certificates, sales tax collection, and inventory tracking — what retail and resale businesses need in year one.
ReadSection 199A lets sole props and S-corps deduct up to 20% of qualified business income. Income thresholds, SSTB rules, and how it interacts with S-corp salary.
ReadWho qualifies, how the exclusive-use test works, simplified method ($5/sq ft) vs actual method compared with real examples, and the S-corp Accountable Plan workaround.
ReadHow to expense the full cost of equipment, software, and vehicles in year one rather than depreciate over 5–7 years. 2025 limits, the SUV cap, and what California doesn't conform to.
ReadHow each plan works, 2025 contribution limits, the December 31 Solo 401(k) establishment deadline, and why Solo 401(k) beats SEP-IRA at almost every income level.
ReadTwo methods to deduct business vehicle use — 70¢/mile standard mileage or actual expense percentage. Which wins for your vehicle, what the mileage log requires, and the SUV and luxury car limits.
ReadEntertainment is no longer deductible after TCJA 2017. Business meals are still 50% deductible with proper documentation. What qualifies, the five documentation requirements, and the employer meal rules.
ReadS-corp owners can't deduct unreimbursed employee expenses on their personal return. An Accountable Plan lets the corporation reimburse you for home office, vehicle, and phone — tax-free to you, deductible by the corporation.
ReadBusiness travel is deductible when the primary purpose is business. The rules differ for domestic trips (>50% business days), international trips (75%+ rule), and mixing personal travel. Full transportation is deductible on primarily-business domestic trips even with personal days added.
ReadThe IRS lets you deduct up to $5,000 in startup costs in year one — but the allowance phases out dollar-for-dollar above $50,000 in total startup costs and disappears entirely at $55,000. Remaining costs are amortized over 180 months.
ReadDistributions are not subject to payroll tax — but only if you're paying a reasonable W-2 salary first. How distributions work, what happens when they exceed your stock basis, and how the IRS evaluates salary/distribution ratios.
ReadLong-term gains are taxed at 0%, 15%, or 20% federally. Short-term gains are ordinary income. California taxes all capital gains as ordinary income — no preferential rate. Combined federal + NIIT + California can exceed 37% on long-term gains for high earners.
ReadPay your minor children for real work and shift income to their lower bracket. In a sole proprietorship, children under 18 are exempt from FICA and FUTA — an additional savings. Earned income also qualifies kids for Roth IRA contributions starting early.
ReadAn NOL carries forward indefinitely under post-TCJA rules — but can only offset 80% of taxable income per year. Pass-through losses also face basis, at-risk, passive activity, and excess business loss limitations before they're deductible.
ReadEducation that maintains or improves skills in your current trade is fully deductible on Schedule C. Education for a new career is not. Continuing education, certifications, conferences, books, and subscriptions — what qualifies and how to deduct it.
ReadExtensions give 6 more months to file — taxes are still due on the original deadline. Filing an extension eliminates the costly failure-to-file penalty (5%/month) but not the failure-to-pay penalty (0.5%/month). When to extend and how to file Form 4868 or 7004.
ReadA filing CPA prepares your return. A planning CPA calls in October with recommendations. What to ask to tell the difference, credentials to verify, red flags to avoid, and what a well-served S-corp owner should expect to pay annually.
ReadSell investment real estate tax-free and reinvest in like-kind property — as long as you identify the replacement within 45 days and close within 180. A qualified intermediary is required. How the basis carries over, boot triggers partial tax, and step-up at death eliminates deferred gain.
ReadReinvest capital gains in a QOZ fund within 180 days to defer the tax. Hold the investment 10+ years and the fund's appreciation is excluded from federal tax entirely. How it compares to a 1031, the 2026 recognition date, and what to watch for in fund quality.
ReadHigh earners above the Roth income limit ($165,000 single / $246,000 MFJ in 2025) can contribute via a two-step backdoor. The pro-rata rule is the primary trap — pre-tax IRA balances make the conversion taxable. How to avoid it by rolling to a Solo 401(k).
ReadContributions reduce AGI (and SE tax), growth is tax-free, qualified withdrawals are tax-free. The only account with all three benefits. 2025 limits ($4,300 self-only / $8,550 family), HDHP requirements, and the stealth retirement account strategy.
ReadLoan proceeds are never income — you owe them back. Business interest is deductible when proceeds were used for business. Forgiven debt is usually taxable income. Shareholder loans from S-corps require written notes and market rates to avoid reclassification.
ReadPass-through owners take charitable deductions on Schedule A, not the business return. Donating appreciated stock avoids capital gains and maximizes the deduction. Donor-Advised Funds, bunching strategy, and the Qualified Charitable Distribution from IRAs.
ReadMulti-member LLCs file Form 1065 and issue K-1s. Active members pay SE tax on their full distributive share — unlike S-corp owners who pay FICA only on W-2 salary. When the S-corp election saves money for a multi-member LLC.
ReadDeduct the business-use portion of your cell phone and home internet on Schedule C. Most service business owners support 60–80% phone and 50–70% internet. S-corp owners must reimburse through an Accountable Plan — no personal deduction after TCJA.
ReadCash basis reports income when received and expenses when paid — it's simpler and defers tax. Accrual matches income and expenses to when they're earned. Most businesses under $30M can use cash basis. Year-end timing strategies that only work on cash basis.
ReadMost small business audits are correspondence audits — a letter asking for documentation on one item. Common triggers include high expense ratios, vehicle deductions without mileage logs, and cash businesses with round-number income. The 3-year statute of limitations, what to send, and why you never respond without a CPA.
ReadPay income tax now, withdraw tax-free forever. Conversions are most powerful in low-income years — a business loss year, the gap before Social Security, or years with large deductions. How to calculate the bracket-fill amount, the Medicare IRMAA surcharge trap, and how business owners use income control to create conversion windows.
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Just getting started
Entity selection, startup runway calculator, first-year tax projection, and the five things to do before your first sale.
SE tax breakdown, S-corp breakeven calculator, and the five mistakes sole props make every year.
SE tax calculator, home office deduction comparison, startup cost write-offs, and everything else you need to know in year one.
True employee cost calculator, payroll deposit rules, contractor vs employee risk, and the trust fund penalty explained.
How to set a defensible reasonable compensation, optimize the W-2 vs distribution split, and understand how the S-corp election interacts with the QBI deduction.
ReadThe moves worth making before Dec 31: retirement contributions, bonus depreciation, QBI optimization, and coordinated loss harvesting.
ReadHow to choose between the three plans, how contribution limits interact with your S-corp salary, and the December 31 deadline that catches owners off guard.
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RSUs, options, K-1s
RSUs, ISOs, NQSOs, K-1s, concentrated positions — when your tax situation crosses seven documents, this guide explains how a CPA and advisor working from the same picture changes what you keep.
“I have RSUs, stock options, K-1s, or concentrated investments.”
RSUs create ordinary income at vesting — not capital gain. The 22% supplemental withholding rate leaves most high earners short. Here's how the math works and what to do about it.
ReadSelling triggers full capital gains. Holding means concentration risk. Five strategies in between — each with different tax, liquidity, and coordination implications.
ReadThe AMT is a parallel tax — you pay whichever is higher. ISO stock option exercises create AMT income even without a sale. The spread at exercise is AMTI; April 15 brings a real tax bill for illiquid private shares. How to model and manage AMT exposure before year-end.
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Business with employees
Deposit schedules, the trust fund penalty, worker classification risk — what most owners with employees don't know until it's too late, with a compliance checker built in.
“I run a business with employees and want to make sure payroll and taxes are handled correctly.”
Small businesses under 50 employees can reimburse employees for individual health insurance premiums and medical expenses — tax-free to employees, deductible to the business. 2025 limits, required notices, and how QSEHRA compares to an ICHRA and group plan.
ReadIssue a 1099-NEC to every contractor, freelancer, or unincorporated vendor paid $600+ in the year. January 31 deadline for both recipient copy and IRS filing. Penalties start at $60/form and escalate to $330/form. Collect W-9s before payment to avoid January scrambles.
ReadMisclassifying an employee as a contractor can mean years of back payroll taxes, penalties, and interest. The IRS three-category test (behavioral, financial, relationship), California's stricter ABC test, Section 530 safe harbor, and the VCSP voluntary reclassification program.
ReadEmployer FICA adds 7.65% per employee on top of salary. Deposits follow strict weekly or monthly schedules — late triggers 2–15% penalties. The trust fund penalty (100% of withheld taxes, personally assessed) is the most dangerous provision in payroll tax law.
ReadThe math behind the fully loaded cost of an employee — FICA, FUTA, SUTA, workers comp, benefits — and how to calculate the revenue a new hire needs to generate to break even.
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Thinking about a sale?
Asset sale vs. stock sale, QSBS eligibility, installment elections, and California exit tax — the decisions that determine how much you actually keep, and why they all have to be made before the LOI.
“I'm thinking about selling in the next few years and want to know what I'd actually keep.”
The five requirements that determine whether your C-corp shares qualify — and how to do the retroactive check before any deal is in motion.
ReadHow installment sales defer capital gain, the gross profit percentage, and the §1245 recapture problem that wipes out the first-year benefit for asset-heavy businesses.
ReadWhy buyers prefer asset sales and sellers prefer stock sales — and how the tax gap between structures can exceed $500K on a $3M deal.
ReadQSBS, S-corp built-in gains, installment elections — several of the highest-value moves require years of lead time. When to start and what to do first.
ReadPersonal vs. enterprise goodwill, why the allocation matters, and how it shows up on the final tax bill.
ReadA walkthrough of the inputs that decide the bill — entity type, asset vs stock, basis, state residency, and deal terms.
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Buying a business
Pre-LOI is cheap exploration — most deal-breakers surface before you spend a dollar on formal due diligence. The LOI is the gate. Cross it without a tax and structure analysis and the cost of fixing it comes out of your purchase price.
“I want to buy a business and I need to know which decisions have to be made before I sign anything.”
Buyers almost always prefer asset sales; sellers almost always prefer stock sales. The tax gap between structures — and how to negotiate it.
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Just launched
SE tax explained, the quarterly payment system from day one, deductions to start tracking now, and why a separate business account is non-negotiable — written for owners in their first year.
“I just started my business and I need to understand how taxes work before I make a mistake.”
15.3% on your net profit, on top of income tax. Why you pay both halves, how the deduction works, and when the S-corp math starts making sense.
ReadWhat estimated taxes are, when they're due, and how to avoid surprise bills by saving the right amount throughout the year.
ReadThe penalty is smaller than you think. The actual math, how to catch up, and the two habits that eliminate this problem permanently.
ReadA simple monthly savings formula, why profit (not revenue) is the right starting point, and how to build a system you'll actually follow.
ReadProfit First, The E-Myth Revisited, Simple Numbers, and a few others — what a CPA actually recommends to clients in year one, and what to skip.
ReadAn LLC is a liability tool, not a tax tool. When it matters, when it doesn't, and the California $800/year detail most people find out too late.
ReadThe ordinary-and-necessary standard, common deductible expenses, and why personal charges don't become write-offs just because they clear the business account.
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Below the S-corp threshold
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Solo service business
SE tax break-even analysis, deductions most solo pros miss, the S-corp question answered with actual math, and a quarterly routine that eliminates April surprises.
“I'm a solo service pro and I'm not sure my setup is costing me money.”
Eight deductions every sole prop and freelancer should be claiming — home office, vehicle mileage, Solo 401(k), health insurance, QBI, and more. Dollar values at $100k and $150k net profit.
ReadSE tax is 15.3% on every dollar of net profit — on top of income tax. How it's calculated, what the deductible half saves, and why the S-corp election is the primary way to reduce it.
ReadSole proprietors take draws — not paychecks. All net profit is taxable whether you withdraw it or not. SE tax is 15.3% on top of income tax. When the S-corp election starts saving money, and what the break-even looks like at different income levels.
ReadAn LLC is a legal structure; an S-corp is a tax election — most S-corp owners have both. When the election pays off, when it doesn't, and what the compliance costs actually are.
ReadForm 2553 timing, salary setup, payroll service selection, and quarterly tax rhythm — the interactive step-by-step checklist for sole props and single-member LLCs making the switch.
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Questions about your specific situation? Book a free 30-minute call with Matt.
Monthly tax planning reminders
One email per month — what’s due, what to do, and which tool to use. No fluff.