How filing status affects your tax

Self-employment tax is the same whatever your filing status. irs.gov Income tax is not, and on $100,000 of profit the difference between single and married filing jointly is about $2,900.

The first half of that sentence surprises people, so it is worth being precise about which part of the bill moves.

What does not move

The 15.3% applies to 92.35% of net profit regardless of who you file with. irs.gov There is no married rate, no head-of-household rate.

One column is constant and the other is not. Every dollar of difference comes from income tax.

What does move, and why

Two mechanisms, and both are about where your income sits rather than what rate applies to self-employment.

The standard deduction. $16,100 single, $32,200 joint, $24,150 head of household. irs.gov Filing jointly removes twice as much income from tax before any bracket applies.

The bracket widths. Joint brackets are roughly twice as wide at the lower end, so more income is taxed at 10% and 12% before reaching 22%.

Head of household sits between the two, which is why it matters so much for a single parent — and why it is worth checking whether you qualify rather than assuming single.

Where the difference lands

The gap widens with income, because the wider joint brackets keep more income out of the higher rates for longer.

Married filing separately is usually worse

At lower incomes the separate figures are identical to single. Above that they get worse, for a reason that catches people: irs.gov

The Additional Medicare Tax threshold is $125,000 for married filing separately, against $200,000 for single and $250,000 for joint. irs.gov That is the one place where filing status does change self-employment tax — at $200,000 of profit, a separate filer pays $28,772 against $28,234 for everyone else.

Separate filing also loses several credits outright and narrows others. It exists for specific situations — liability separation, a spouse with tax debt, income-driven student loan repayment — and those reasons are rarely about the tax arithmetic itself.

The QBI threshold moves too

The income level where the qualified business income deduction starts phasing out is $201,750 for single and head of household, and $403,500 for joint. irs.gov

Married filing separately is $201,775. Twenty-five dollars above single, which looks like a transcription error and is not. The QBI deduction covers what happens either side of that line.

What to actually do with this

Check head of household if you are single with a dependent. The requirements are specific — paying more than half the cost of a home for a qualifying person.

Do not choose separate filing to protect yourself from a spouse’s freelance income. It rarely helps and usually costs. Innocent spouse relief exists for the situation people are usually worried about.

Remember your spouse’s income sets your brackets. Filing jointly with a high earner means your freelance profit is taxed at their marginal rate, not at the rate it would face alone. That does not make joint filing wrong — it is still cheaper overall — but it is why the marginal cost of another project is higher than a single filer’s at the same profit.

Related: self-employment tax explained · the QBI deduction · the wage base cap · run your numbers