Contracting vs Full-Time Employment: What's the Real Arithmetic?
FinTech

Contracting vs Full-Time Employment: What's the Real Arithmetic?

A contracting rate that looks 40% higher than a salary isn't 40% higher take-home. Here's the actual math the IRS publishes, and the pieces that don't show up on either side's headline number.

Published December 11, 202510 min readUpdated Sep 6, 2026

Written by · Full-Stack Agentic AI Software Engineer — AI Agents, Automation & Revenue Systems for GTM/RevOps teams

In brief

What's the actual financial arithmetic between contracting and full-time employment for a software engineer in the US?

A contracting rate has to clear more hurdles than a salary before it's comparable: the self-employer pays both halves of the Social Security and Medicare tax the IRS calls self-employment tax, currently a combined 15.3% of net earnings up to the annual Social Security wage base, gets no employer-subsidized health insurance or 401(k) match, and carries no unemployment insurance if the contract ends early. Against that, a contractor can deduct real business expenses before tax and, since the One Big Beautiful Bill Act, claim a permanent Section 199A deduction on qualified business income — 20% for 2025, rising to 23% for tax years after 2025. None of this says which structure is better; it depends on income stability, health coverage needs, and how the reader's own state and situation treat the deductions. This is general information about US federal tax mechanics, not tax advice, and jurisdiction changes the whole calculation.

  • Self-employment tax in the US is 15.3% of net self-employment earnings, combining the 12.4% Social Security and 2.9% Medicare components, per current IRS guidance
  • The 12.4% Social Security portion applies only up to the annual wage base (recently $168,600); the 2.9% Medicare portion has no cap and an additional 0.9% applies above income thresholds that vary by filing status
  • A W-2 employee's employer pays half of the equivalent payroll tax invisibly — that's the piece a headline rate comparison misses most often
  • The Section 199A qualified business income deduction is now permanent under the One Big Beautiful Bill Act: 20% for 2025, rising to 23% for tax years after 2025, subject to income phase-outs
  • The IRS classifies workers as employee vs independent contractor using behavioral control, financial control, and relationship-type factors — no single factor decides it, and misclassification has real consequences for both sides
  • BLS's Contingent Worker Supplement found independent contractors had lower health insurance coverage (74.2%) than traditional employees (84.9%) in its most recent fielded survey, a real gap in benefits access, not a stereotype

Evidence notes

IRS, "Self-Employment Tax (Social Security and Medicare Taxes)"

Current combined self-employment tax rate is 15.3%: 12.4% for Social Security and 2.9% for Medicare. The Social Security portion applies to the first $168,600 of combined wages and self-employment income; above that threshold only the 2.9% Medicare portion continues. An additional 0.9% Medicare tax applies above filing-status-specific thresholds ($125,000 to $250,000).

IRS, "Independent Contractor (Self-Employed) or Employee?"

The IRS weighs three categories with no single deciding factor: behavioral control (does the company control how the work is done), financial control (who bears the business's financial risk and provides tools/expenses), and the type of relationship (written contracts, benefits, permanence, and whether the work is integral to the business).

One Big Beautiful Bill Act, Section 199A changes (signed July 2025)

Made the qualified business income deduction permanent with no expiration date. The deduction rate is 20% of qualified business income for 2025, rising to 23% for tax years beginning after December 31, 2025. Income phase-out thresholds for 2025 are $494,600 (married filing jointly) and $247,300 (other filers); phase-in ranges widen starting 2026.

US Bureau of Labor Statistics, Contingent Worker Supplement (fielded July 2023, most recent published detail)

74.2% of independent contractors reported having health insurance coverage, versus 84.9% of workers in traditional employment arrangements. Independent contractors also skewed older: 36% were age 55 or older.

Continue with purpose

A recruiter quotes a contract rate 40% above your current salary, annualized. That sounds like a raise. It usually isn't one, and the gap between the two numbers is entirely mechanical — it's tax structure and missing benefits, not negotiation.

This isn't an argument for one structure over the other. It depends on your income stability needs, your health coverage situation, and your own state and tax position — this is general information about how the US federal mechanics work, not tax advice, and it changes if you're outside the US. Much of the judgment contracting vs full-time employment demands shows up as process design, which is what publishes on. Much of the judgment contracting vs full-time employment demands shows up as process design, which is what XenGrowth publishes on.

The tax that doesn't show up on a W-2

Every paycheck, a W-2 employee in the US pays 7.65% of wages toward Social Security and Medicare, and the employer quietly matches that with another 7.65% that never touches the employee's pay stub. Per the IRS's guidance on self-employment tax, a self-employed person pays both halves directly: a combined 15.3% self-employment tax, split into 12.4% for Social Security and 2.9% for Medicare, on net self-employment earnings.

The 12.4% Social Security portion only applies up to the annual wage base — recently $168,600 — after which just the uncapped 2.9% Medicare portion continues. High earners also owe an additional 0.9% Medicare surtax above filing-status thresholds ranging from $125,000 to $250,000. None of this is a penalty for contracting. It's the same total tax a W-2 job pays; it's just that the employer's invisible half becomes visible the moment you're the one writing both checks.

Component

W-2 employee

1099 contractor / self-employed

Social Security + Medicare

7.65% withheld, employer pays matching 7.65% invisibly

15.3% self-employment tax paid entirely by the worker (up to the SS wage base for the 12.4% portion)

Health insurance

Often subsidized by employer group plan

Purchased individually unless covered elsewhere

401(k) match

Common, effectively free money

None — any retirement contribution is fully self-funded

Unemployment insurance

Employer-funded, available if laid off

Not available if a contract ends early

Business expense deductions

Largely unavailable (post-2017 tax law)

Real equipment, software, and workspace costs deductible against income

Section 199A QBI deduction

Not applicable

20% of qualified business income for 2025, rising to 23% for tax years after 2025

How the IRS decides which one you actually are

This isn't just a matter of what your contract calls you. The IRS's own classification guidance weighs three factors, with no single one deciding it: behavioral control (does the company control how, not just what, the work gets done), financial control (who bears the business risk, and who provides equipment and covers unreimbursed expenses), and the type of relationship (written contracts, permanence, whether benefits are offered, and whether the work is core to the business rather than incidental to it). There is a longer treatment of the operations side of this in . There is a longer treatment of the operations side of this in The XenGrowth resource library.

Misclassification cuts both ways. A company that treats someone as a contractor while directing their hours, tools, and daily work like an employee risks back taxes and penalties if the IRS disagrees. A worker misclassified as a contractor loses access to unemployment insurance and employer-side tax contributions they may not realize they were owed. If your actual working arrangement looks more like employment than independent contracting — set hours, company equipment, ongoing indefinite work — that's worth raising before it becomes a compliance problem for either side. The company-side version of this arithmetic, including where a contractor genuinely costs less and where it doesn't, is covered in this cost model comparing an agent, a contractor, and a full-time hire.

The deduction that changed in 2025

Section 199A of the US tax code lets owners of pass-through businesses — which includes most independent contractors operating as sole proprietors or through an LLC — deduct a share of their qualified business income before tax. The One Big Beautiful Bill Act, signed in July 2025, made this deduction permanent with no expiration date: 20% of qualified business income for 2025, rising to 23% for tax years beginning after December 31, 2025. For 2025 the deduction phases out entirely above $494,600 in taxable income for joint filers and $247,300 for other filers, with wider phase-in ranges starting in 2026.

This is real money and it's specific to the US federal code — it doesn't exist for a W-2 employee's wage income, and it doesn't transfer to a different country's tax system. Anyone reading this outside the US should treat 199A as an illustration of how a self-employment deduction can work, not a rule that applies to them.

The benefits gap is real, not a stereotype

It's tempting to wave away the benefits difference as something a high enough rate covers. The BLS's Contingent Worker Supplement — fielded most recently in July 2023 as a supplement to the Current Population Survey — found 74.2% of independent contractors reported having health insurance, against 84.9% of workers in traditional employment arrangements. That's not proof contractors can't get covered; it's evidence that a meaningful share genuinely go without or pay for it entirely out of pocket, and that cost belongs in the arithmetic, not in a footnote. covers the AI agents and marketing automation side of this. XenGrowth on AI agents and marketing automation covers the AI agents and marketing automation side of this.

  1. Price your own health coverage before comparing rates, not after — this is often the single largest gap between a contract rate and a comparable salary

  2. Model the employer 401(k) match you'd be giving up as a real percentage reduction in total compensation, not a nice-to-have

  3. Treat unemployment insurance as real, if unlikely-feeling, insurance — a contract that ends early has no safety net behind it the way a layoff from a W-2 role does

  4. Only after those three, apply the Section 199A deduction and your real deductible expenses to see what the after-tax comparison actually looks like

The rate is not the offer. The rate minus the tax structure minus the missing benefits is the offer.

A worked comparison, mechanically, not as advice

None of the following is a recommendation for what a real number should be — it's an illustration of which line items actually move between the two structures, using round figures so the mechanism is visible rather than the arithmetic of any specific offer. Picture a salaried role paying $150,000 and a contract quoted at $190,000 annualized, a 27% headline gap that's the kind of number that gets a contract offer accepted on the spot.

Line item

$150,000 salary (illustrative)

$190,000 contract (illustrative)

Employer-side payroll tax

Paid by employer, invisible to the worker

None — no employer exists to pay it

Self-employment / employee-side FICA

7.65% withheld from pay

15.3% owed directly on net earnings

Health insurance

Often partly employer-subsidized

Purchased individually, full cost borne by the worker

Retirement match

Common, e.g. employer matches a percentage

None — any contribution is entirely self-funded

Unemployment insurance

Available if the role ends involuntarily

Not available if the contract ends early

Section 199A deduction

Not applicable to W-2 wages

Applies to qualified business income, reducing taxable income

Run every one of those rows and the 27% headline gap compresses substantially before a single dollar of state tax or actual expense deduction gets involved. It doesn't necessarily vanish — a genuinely strong contract rate can still come out ahead after all of this, especially with real deductible expenses behind the 199A deduction — but the point is that the comparison has to happen at this level of detail before either number means anything. Comparing $190,000 to $150,000 directly is comparing two different kinds of number wearing the same currency symbol.

What estimated taxes change about the cash-flow picture

A W-2 employee's tax bill is withheld automatically, spread evenly across every paycheck. A contractor's isn't withheld by anyone, which means the same 15.3% self-employment tax plus ordinary income tax has to be paid proactively, in quarterly installments, or an underpayment penalty applies. That timing difference doesn't change how much is owed — it changes how disciplined the cash management around it has to be, which is a real cost most rate comparisons never mention. Building the discipline to hold that money aside is closer to the budgeting question covered in how much you're actually able to save versus earn than it is to a tax-specific problem. works through AI search, GEO and discovery in more operational detail. XenGrowth on AI search, GEO and discovery works through AI search, GEO and discovery in more operational detail.

State taxes are a separate calculation entirely

Everything above is federal. US state tax treatment of self-employment income, business deductions, and even the availability of an S-corp election to reduce self-employment tax exposure varies enormously by state, and some states impose their own franchise or business taxes on a sole proprietorship or LLC that a W-2 employee never encounters. None of that is covered here, and it shouldn't be guessed at — it's a question for a tax professional licensed in the reader's own state, not a general post that can't see which state that is.

What this arithmetic doesn't decide for you

None of this says contracting or full-time employment is the right structure for you. It depends on how much you value predictable income versus a potentially higher rate, whether you can get health coverage another way, whether you have real deductible expenses to offset the tax gap, and how comfortable you are running your own tax administration. This is general information about how the US federal tax mechanics work, not financial or tax advice — your own state's rules, your specific income level, and your actual contract terms all change the answer, and someone outside the US is working from an entirely different rulebook. For a broader look at how companies structure and budget for contractor relationships, covers the operations side of that decision.

What's not in question is the mechanical fact underneath all of it: a contract rate and a salary are not the same kind of number, and comparing them without running the tax and benefits math first is comparing gross to net. Teams that plan headcount and contractor spend against a real revenue model are covered in .

Further reading from XenGrowth

Where this work meets go-to-market

If you're weighing this from the hiring side rather than the contractor side, publishes operator guides on building and staffing go-to-market teams, contractors included.

Further reading from XenGrowth

Where this work meets go-to-market

writes for the teams who have to run contracting vs full-time employment day to day.

Further reading from XenGrowth

Where this work meets go-to-market

the team at XenGrowth writes for the teams who have to run contracting vs full-time employment day to day.

Which structure fits what you actually need right now?

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