Commission Calculator

How a commission is calculated

A commission is a share of a sale paid to the person who closed it. The base arithmetic is one multiplication: sale amount times commission rate. A $20,000 sale at 4% pays $800. Everything else on this page is a variation on that line, and the variations are where most disputes start.

Three numbers decide what lands in your pocket:

• Commissionable sale. The amount the rate applies to. It may be the full sale, the sale minus taxes and shipping, or the sale minus returns.
• Rate structure. A flat percentage, a tiered schedule, or a rate that changes once a quota is met.
• Split. The share of the commission that belongs to you when more than one person worked the deal.

The effective rate is the number to watch. It is total commission divided by total sales, and it tells you what you earned per dollar sold. A 5% base rate with an 8% tier above $10,000 produces an effective rate of 5.6% on a $12,500 sale, because only the top slice earns the higher rate. Sales reps who quote the top rate as their earnings are usually quoting a number they will not hit on an average deal.

This calculator handles a flat rate, a two-tier schedule and a split in one pass, and it nets out refunds before it applies the rate. That last step is the one most spreadsheets get wrong.

Worked example: a $12,500 sale on a tiered plan

The plan pays 5% on the first $10,000 of a sale and 8% on anything above that. The sale is $12,500 and one rep gets the full commission.

The first tier takes the lower rate on the first $10,000: 10,000 x 0.05 = $500. The second tier takes the higher rate on the remaining $2,500: 2,500 x 0.08 = $200. Total commission is 500 + 200 = $700. The effective rate is 700 / 12,500 = 5.6%.

Compare that with a flat 5% plan, which pays 12,500 x 0.05 = $625. The tier is worth $75 on this sale, not the $375 that a rep might expect from applying 8% to the whole amount. The difference between marginal tiers and whole-sale tiers is the single most common misunderstanding in commission plans, and it is worth confirming in writing before you accept an offer.

Push the same plan to a $25,000 sale and the tier does more work. The first $10,000 pays $500, the remaining $15,000 pays 15,000 x 0.08 = $1,200, and the total is $1,700, an effective rate of 6.8%. Below the threshold the plan behaves like a flat 5%: an $8,000 sale pays 8,000 x 0.05 = $400 and no tier applies at all.

Tiered rates: marginal, retroactive and quota-based

Tiered plans come in two shapes, and they pay different amounts on the same sale. A marginal tier pays the higher rate only on the portion above the threshold, the way income tax brackets work. A retroactive tier pays the higher rate on the entire sale once the threshold is crossed. The table uses a 5% base, an 8% tier above $10,000, and no split.

A retroactive tier creates a cliff. At $9,999 the commission is $499.95 at the flat rate, and at $10,001 it jumps to $800.08 under a retroactive 8%. That $300 jump for two dollars of extra sales is why retroactive tiers are usually paired with a quota period rather than a single deal, so the threshold applies to a month or a quarter of accumulated sales instead of one invoice.

Quota-based plans work the same way on a monthly total. Sell $80,000 against a $100,000 quota and you are paid at the base rate on all of it. Cross the quota and the rate may step up on everything, or only on the amount above it. Ask which one, because on an $80,000 month the difference between the two can be several thousand dollars.

Splits: two people, one commission

When two reps work one deal, the commission is divided by an agreed percentage. The split applies to the commission, not to the sale, so the arithmetic is simple once you know the gross figure. Take the $12,500 sale at a flat 6%, which pays $750. A 60/40 split gives the lead rep 750 x 0.60 = $450 and the second rep 750 x 0.40 = $300.

The order of operations matters when a tier is involved. Split the sale first and each rep's tier is calculated on their own slice, which usually pays less in total because neither slice crosses the threshold. Split the commission after the tier is calculated on the whole sale and the pair keeps the full tier benefit. Most plans do the second, but plenty do the first, and the gap on a $12,500 deal is $75.

Splits also show up in referral fees, house accounts and team pools. A common structure is 50% to the rep who closes, 25% to the one who sourced the lead, and 25% to a house pool. On the $700 tiered example, that is $350, $175 and $175. Whatever the structure, write the percentages into the plan document. Verbal splits are the source of more payroll disputes than any rate change.

Refunds, returns and chargebacks

Commission is usually paid on sales, not on cash collected, which means a refund creates a clawback. The customer gets their money back, and the commission that was paid on that sale is reversed, either in full or proportionally. The table shows a $12,500 sale at a flat 6%, which pays $750, with three different refund sizes.

The proportional method is the fair one and the one most plans use: commission is recalculated on the net sale. A plan that claws back the full commission on a partial return is punishing the rep for a $200 return on a $12,500 sale, and that is worth pushing back on when a plan is being written.

Chargebacks are different. A chargeback is a disputed card payment that the bank reverses, and it usually arrives with a fee on top, often $15 to $25 per dispute depending on the processor. Many plans deduct both the sale and the fee from the next commission run. Keep documentation for every disputed order, because the rep is often the only person who can prove the delivery happened. The Federal Trade Commission's Cooling-Off Rule guidance explains the three day cancellation window that applies to some in-home sales, which is one legitimate source of refunds a rep cannot prevent.

What withholding does to a commission check

A commission is taxed as ordinary income, but it is withheld differently from a salary. The IRS treats commission paid separately from regular wages as supplemental wages, and the flat withholding rate on supplemental wages is 22% for 2026, per Publication 15. That 22% is a withholding rate, not a tax bracket. If your marginal rate is higher, you settle up at filing time.

The flat rate applies to supplemental wages up to $1 million in a calendar year. Above that the rate rises to 37%. Most sales reps never see the second rate, but a large one-time bonus can push a single payment over the line, and the payroll system will withhold at the higher rate on the excess.

On a $700 commission paid separately, the federal withholding is 700 x 0.22 = $154, leaving $546 before Social Security, Medicare and state tax. Social Security takes 6.2% and Medicare 1.45%, which is another $53.55 on this check. If you are a 1099 contractor rather than a W-2 employee, nothing is withheld, and you owe self-employment tax of 15.3% on 92.35% of net earnings plus income tax, as the IRS explains on its self-employment tax page. On $700 that is roughly $99 before income tax, so set it aside.

Commissions also change your withholding math for the year. A single large payment withheld at 22% can leave you underwithheld if your total income lands in the 24% bracket or higher. Check the total in the fall and adjust a W-4 if the gap is large.

Draws, guarantees and recoupment

Some sales jobs pay a draw against future commission. A recoverable draw is an advance: you get $2,000 a month while you build a pipeline, and future commissions repay it before you see new money. A non-recoverable draw is a floor, and you keep it even if the commission never covers it.

The distinction matters at the end of a job. Leave with a $4,000 recoverable draw outstanding and the employer may deduct it from your final commission check, which can mean a last paycheck of zero. Leave with a non-recoverable draw and the balance is the company's problem. Get the word "recoverable" or "non-recoverable" in the offer letter, not in a verbal explanation.

Guarantees work the other way. A new hire guarantee might pay $3,000 a month for the first 90 days regardless of sales, then switch to commission. During the guarantee period, commission is often still tracked and paid on top, or it is credited against the guarantee. Ask which, because the two arrangements produce different checks in month four.

Checking a commission statement line by line

Most commission errors are small and repeat every month, which makes them worth finding. Work through the statement in this order.

• Gross sales. Compare the total to your own order records. Missing orders are the most common error and the easiest to prove.
• Returns and adjustments. Check that each refund matches a real return and that the clawback is proportional, not the full commission.
• Rate applied. Confirm the tier threshold and whether the plan is marginal or retroactive. A plan applied as marginal when it should be retroactive shortchanges the rep on every deal above the threshold.
• Splits. Verify the percentage and the person. A split assigned to the wrong rep is usually corrected quietly the next month, but only if someone asks.
• Withholding. Check the 22% federal line on separately paid commission, and confirm that Social Security and Medicare were taken at 6.2% and 1.45%.

Keep a running spreadsheet with one row per deal: date, customer, sale amount, rate, commission, split and paid date. When a statement looks short, you can point to the exact row instead of describing a feeling. That single habit resolves most disputes in one email, and it makes the annual review conversation much shorter.

This page is a planning tool, not tax or legal advice. Commission plans are contracts, and the terms in your plan document control the payout.