Self-Employment Tax Explained: What the 15.3% SE Tax Actually Is and How to Reduce It

Disclaimer: This article provides general educational information about self-employment tax. It is not tax advice. Your specific SE tax obligation depends on your net earnings and filing situation. Consult a licensed CPA before making business structure or tax decisions.

In This Article

1. What Is Self-Employment Tax?
2. How Is Self-Employment Tax Calculated on Schedule SE?
3. Can I Deduct Half of My Self-Employment Tax?
4. What Strategies Do CPAs Use to Reduce Self-Employment Tax?
5. How Does New Jersey Tax Self-Employment Income?
6. Self-Employment Tax Quick Reference Summary
7. Frequently Asked Questions
8. Ready to File With Confidence?

What Is Self-Employment Tax?

Self-employment (SE) tax is the mechanism by which self-employed individuals contribute to Social Security and Medicare: the same programs that W-2 employees fund through FICA withholding.

When you work as an employee, the Social Security and Medicare taxes are split between you and your employer:

• Employee pays: 7.65% (6.2% Social Security + 1.45% Medicare)
• Employer pays: 7.65% (matching contribution)

When you're self-employed, you wear both hats. You pay both the employee and employer share, which is where the 15.3% rate comes from. Freelance developers and content creators deal with this every quarter.

How Is Self-Employment Tax Calculated on Schedule SE?

SE tax is reported on Schedule SE. For an ordinary nonfarm sole proprietor, Schedule C profit (gross business income minus deductible business expenses) enters Schedule SE line 2 and is generally multiplied by 92.35% to determine line 4c net earnings from self-employment. Those are two distinct quantities; the 92.35% factor is not applied a second time to an amount already defined as Schedule SE net earnings.

The Rate Breakdown

• 12.4% Social Security tax applies to Schedule SE line 4c net earnings only within the taxpayer's remaining combined Social Security wage base ($184,500 for 2026 after W-2 wages)
• 2.9% Medicare tax applies to Schedule SE line 4c net earnings without that wage-base cap
• 0.9% Additional Medicare Tax is calculated separately on Form 8959 when combined Medicare wages, railroad compensation, and self-employment income exceed $200,000 single or $250,000 married filing jointly

For a taxpayer with no W-2 wages and business profit below the 2026 wage base, the regular Schedule SE calculation is generally Schedule C profit x 92.35% x 15.3%.

The 92.35% Rule

For an ordinary nonfarm sole proprietor, Schedule SE generally multiplies Schedule C profit by 92.35% (100% minus 7.65%) to determine line 4c net earnings before applying the regular Social Security and Medicare rates. This mirrors the employer-equivalent adjustment. Do not multiply an amount already defined as Schedule SE net earnings by 92.35% again.

SE Tax Formula:

1. Schedule C profit = Gross business income minus deductible business expenses
2. Schedule SE line 4c net earnings = Schedule C profit x 92.35% (ordinary nonfarm method)
3. Regular SE tax = 12.4% Social Security on line 4c within the remaining combined wage base + 2.9% Medicare on line 4c; Form 8959 separately tests Additional Medicare Tax

Example: You earn $80,000 net from freelancing in 2025.

• SE tax base = $80,000 × 92.35% = $73,880
• SE tax = $73,880 × 15.3% = $11,304

This is on top of your regular federal income tax and NJ state income tax.

Can I Deduct Half of My Self-Employment Tax?

Here's one immediate benefit: you can deduct half of your SE tax as an above-the-line deduction on Schedule 1 of Form 1040. This reduces your Adjusted Gross Income (AGI), which reduces your income tax (but not the SE tax itself).

In the example above: Half of $11,304 = $5,652 deduction. If you're in the 22% tax bracket, this saves you $5,652 × 22% = $1,243 in income tax.

What Strategies Do CPAs Use to Reduce Self-Employment Tax?

SE tax is a significant expense, often $10,000–$25,000+ per year for freelancers earning $100K–$200K. Here are the primary strategies:

Strategy 1: Maximize Business Deductions

For an ordinary Schedule C business, deductible business expenses reduce Schedule C profit before that profit enters the Schedule SE line 4c computation. That generally reduces both income tax and regular SE tax, subject to the wage-base and other return-specific mechanics.

Common overlooked deductions for freelancers:

• Home office (regular and exclusive use, simplified or actual expense method)
• Vehicle mileage for business use ($0.725/mile Jan-Jun 2026 / $0.76/mile Jul-Dec 2026, $0.70/mile for 2025)
• Professional development, courses, certifications
• Business-use portion of phone and internet
• Equipment, software, and tools
• Health insurance premiums (deductible as an above-the-line deduction)
• Retirement plan contributions (SEP-IRA, Solo 401k, see below)

Strategy 2: Contribute to a Tax-Advantaged Retirement Account

Self-employed individuals can contribute to a SEP-IRA (25% plan rate - effectively about 20% of net self-employment profit, max $72,000 for 2026) or a Solo 401(k) (up to $24,500 employee contribution + 25% employer contribution, max $72,000 for 2026). These contributions are deductible from income tax but do not reduce SE tax. They reduce your AGI, which reduces your income tax bracket.

Strategy 3: Elect S-Corporation Status

An S-Corp election can reduce payroll-tax exposure when reasonable compensation is below business profit, but it is not automatically the best strategy at a fixed profit level.

Here's how it works:

• As a sole proprietor, Schedule C profit generally is multiplied by 92.35% to determine Schedule SE line 4c net earnings
• As an S-Corp, you pay yourself a reasonable W-2 salary (e.g., $60,000)
• Only the salary portion is subject to FICA/SE tax
• The remaining profit is distributed as an S-Corp distribution, not subject to SE tax

Example: You net $120,000 as a sole proprietor.

• Sole-proprietor regular SE tax, assuming no W-2 wages: $120,000 x 92.35% = $110,820 line 4c net earnings; $110,820 x 15.3% = $16,955.46
• After S-Corp election with $70,000 salary: FICA on $70,000 ≈ $10,710. The remaining $50,000 distribution avoids SE tax entirely.
• The $16,955.46 minus $10,710 payroll-tax comparison is a $6,245.46 gross payroll-tax difference, not net savings

The net result must include the employer payroll-tax deduction, federal income tax, QBI, NJ payroll and income taxes, other wages, reasonable-compensation support, payroll, separate returns, and professional fees. No universal $60,000 or $80,000 profit threshold replaces that full model.

Strategy 4: Track Everything in Real Time

The biggest SE tax reduction strategy is also the simplest: don't miss deductions. Many self-employed individuals understate their business expenses simply because they don't have a system for tracking them. Using QuickBooks or a similar platform, or working with a bookkeeper, ensures you capture every deductible item.

How Does New Jersey Tax Self-Employment Income?

New Jersey does not have a separate SE tax (the SE tax is a federal-only tax). However, NJ income tax applies to your net self-employment income at NJ's graduated rates (1.4% to 10.75%). NJ also requires quarterly estimated payments if you expect to owe more than $400 in NJ tax after withholding and credits.

NJ does not conform to several federal above-the-line deductions. NJ treatment depends on the plan. Solo 401(k) employee deferrals ARE excludable from NJ gross income per N.J.S.A. 54A:6-21; NJ guidance does not clearly address employer (match/profit-sharing) contributions to a Solo 401(k) - confirm that share for your facts. SEP-IRA and SIMPLE IRA contributions are NOT deductible for NJ purposes (N.J.S.A. 54A:6-26 for IRAs); they create NJ basis recoverable tax-free in retirement under the 3-Year Rule or General Rule. For health insurance, NJ has its own statute: N.J.S.A. 54A:3-5 lets self-employed individuals deduct premiums on the NJ-1040 (via Worksheet F, NOT subject to the 2% medical floor, capped at earned income from the business). NJ does NOT conform to §164(f) half-SE-tax. A CPA familiar with NJ tax law will make sure your NJ-specific calculations are right.

Self-Employment Tax Quick Reference Summary

Monaco CPA works with freelancers, independent contractors, and self-employed professionals throughout New Jersey to minimize SE tax through proper deduction tracking, retirement planning, and entity structuring.

OBBBA update (July 2025): The One Big Beautiful Bill Act made the TCJA individual income tax rates permanent. The 37% top bracket, which was set to revert to 39.6% in 2026, is now the permanent rate. This matters for self-employed individuals because SE income flows through to your personal return at these rates. The permanent rate structure provides more certainty for multi-year tax planning.

Run the numbers: Use the free S-Corp Savings Calculator to see how much S-Corp election could reduce your SE tax burden. You can also estimate your current SE tax with the Self-Employment Tax Calculator.

Greg Monaco, CPA, MBA is the founder of Gregory Monaco, CPA LLC, a virtual CPA practice based in Livingston, NJ. Member of AICPA and NJCPA.

Frequently Asked Questions

Ready to File With Confidence?

Tax rules change frequently. If anything in this guide applies to your situation, a quick review with a CPA can prevent costly mistakes. Greg Monaco is a NJ-licensed CPA (License #20CC04711400). Greg remains responsible for every engagement and reviews, approves, and signs all client-facing work. Trained staff may assist under his direct supervision and confidentiality procedures.

Use the contact form