Do Resellers Pay Quarterly Taxes? How Much to Set Aside and When

Who has to pay estimated tax

The 2026 Form 1040-ES gives the general rule. In most cases you must pay estimated tax for 2026 if both of these apply:

1. You expect to owe at least $1,000 for 2026 after subtracting withholding and refundable credits.
2. You expect your withholding and refundable credits to be less than the smaller of 90% of the tax on your 2026 return, or 100% of the tax on your 2025 return. If your 2025 adjusted gross income was over $150,000 ($75,000 if married filing separately), use 110% instead of 100%.

Two related points from the same form:

• No 2025 tax, no requirement. You don’t have to pay estimated tax for 2026 if you were a U.S. citizen or resident alien for all of 2025 and had no tax liability for that full year.
• Withholding can do the job. If you also have a job, the form says you may be able to skip estimated payments by having your employer withhold more, using a new Form W-4.

The 2026 due dates

Form 1040-ES says you don’t have to make the January 15, 2027 payment if you file your 2026 return by February 1, 2027 and pay the full balance with it. The form says a penalty may apply if you didn’t pay enough for the year or didn’t pay on time or in the required amount, and it’s figured on each underpayment for the days it stays unpaid. If a large change in income after March 31 means you need to start paying, the form points to the annualized income installment method (Pub. 505, filed with Form 2210 and its Schedule AI).

You can pay online (the form points to IRS.gov/ModernPayments) or mail a check with a 1040-ES voucher. You can also pay more often than four times, as long as the total paid in each period reaches the amount due by that period’s date. If your state has an income tax, check its revenue department for its own estimated-payment rules and dates.

Self-employment tax: the part that’s easy to miss

Income tax is only part of it. A reseller with a Schedule C profit also owes self-employment tax, which is Social Security and Medicare for people who work for themselves. From the IRS self-employment tax page and Publication 334:

• The rate is 15.3%: 12.4% Social Security plus 2.9% Medicare.
• It applies to 92.35% of your net profit, your net earnings from self-employment.
• It applies only if those net earnings are $400 or more.
• The Social Security part stops at the wage base, which is $184,500 for 2026; wages subject to Social Security count toward it. Medicare has no cap, and an extra 0.9% Medicare tax applies above $200,000 (single or head of household), $250,000 (married filing jointly) or $125,000 (married filing separately).
• You deduct the employer-equivalent half of self-employment tax when you figure adjusted gross income.

Worked example: $9,115 of profit

Take a seller whose 2026 Schedule C shows $30,000 of gross sales and $500 of returns. Cost of goods sold is $11,000: $3,000 beginning inventory plus $12,000 of purchases, less $4,000 ending inventory. Expenses are $9,385: $4,000 of fees, $3,500 of labels, $400 of supplies, and $1,485 of mileage (1,000 miles at 72.5¢ plus 1,000 at 76¢). That leaves a net profit of $9,115. The seller is single, has no W-2 wages and uses 12% as an example top federal rate. Here is what our set-aside calculator returns:

That’s 25.3% of the profit. With a 5% state income tax added on the same base ($423.55), the total becomes $2,727.98, or 29.9%, which is $682.00 a quarter. The total is over $1,000. Unless withholding or the prior-year rules above cover it, this seller is in estimated-tax territory.

The $400 line

Self-employment tax switches on sharply. A profit of $433.13 gives net earnings of $399.9955, just under $400, so there’s no self-employment tax. One more cent, $433.14, gives net earnings of exactly $400.00 and self-employment tax of $61.20. Income tax is a separate question with its own filing rules, and Publication 334 notes that you may have to file a return for other reasons even below $400.

Why a flat percentage is only a start

Advice like “set aside 25%” is a reasonable first guess. Here is how far the real share moves, with every row from the same calculator:

In the fifth row, wages already use up most of the $184,500 wage base, so Social Security applies only to $14,500 of the profit. In the last row, the extra 0.9% Medicare tax starts. Several things that affect real tax aren’t in any row: tax brackets, credits, your state’s rules, and the qualified business income deduction. P.L. 119-21, sec. 70105 made that 20% deduction permanent, and Pub 334 confirms it. It can lower income tax on Schedule C profit, but it depends on your whole return, so our calculator leaves it out.

One simple routine: after each payout, move the estimated share into a separate account, then pay from it on the four dates. Recheck the share whenever your profit or other income changes.

Next step

Put your expected 2026 profit, filing status, wages and top rate into the reseller tax set-aside calculator. It shows the quarterly amount and these due dates. If you’re unsure whether your selling is a business at all, start with hobby or business. The inventory guide explains how cost of goods sold shapes the profit figure.