Invoice Factoring Calculator: Advance, Fee & Effective APR

See the real annualized effective APR behind a factoring company's flat discount rate.

Factoring companies quote their fee as a flat percentage per invoice — 3% for a 30-day invoice, say — which looks small next to a loan's annual percentage rate until you actually annualize it. This estimator does that conversion explicitly, turning the flat per-invoice discount into an effective APR using the same day-count method the trade-finance industry uses, so a factoring quote and a bank loan's APR land on comparable ground.

How to estimate invoice factoring costs

Enter the invoice's face value in dollars.
Enter the factor's discount rate (its fee) as a percentage, and the advance rate — the share of the invoice it pays you upfront.
Enter the number of days you expect your customer to take to pay, or leave the field blank to use the 30-day default.
Read the six result boxes: invoice amount, advance amount, fee amount, net amount received, the days used, and the effective APR.

Worked example: 3% on a 30-day invoice

Start with the calculator's own defaults: a $10,000 invoice, a 90% advance rate and a 3% discount rate. The advance is $10,000 × 90% = $9,000. The fee is 3% of that advance, $270, so $8,730 lands in your account on day one.

If the customer pays in 30 days, the effective APR is 3 ÷ 30 × 365 = 36.5%. Keep every other input the same and set 15 days, and the APR doubles to 73.0%; at 60 days it falls to 18.3% (18.25% before rounding). The $270 does not change in any of the three cases — only the length of time you are paying it for does, and a flat fee spread over fewer days is a more expensive way to borrow.

Why a flat 3% fee isn't a 3% APR

The discount rate a factor quotes is charged once, for however long the invoice takes to get paid — not per year. Annualizing it means dividing the discount rate by the actual number of days to payment and multiplying by 365, which is the standard way the factoring and trade-finance industry expresses a short-holding-period fee on the same annual basis a bank loan's APR uses.

That conversion is sensitive to the days-to-payment figure in a way that surprises people: the same 3% fee on an invoice paid in 15 days annualizes to roughly double the APR of one paid in 30 days, because the cost is fixed but the holding period it's spread over is half as long.

Advance rate, fee, and what actually lands in your account

The advance amount is the invoice value multiplied by the advance rate — commonly 80 to 90% in real factoring arrangements — and that is the base this calculator takes the fee from, not the full invoice face value. The fee is the advance amount multiplied by the discount rate, and the net cash you actually receive upfront is the advance amount minus that fee.

Many factors instead quote the fee on the invoice's face value, which makes the dollar fee larger: 3% of $10,000 is $300, not the $270 shown above. To match a face-value quote here, enter the discount rate divided by the advance rate — 3 ÷ 0.9, entered as 3.333% at a 90% advance. The fee then comes out at about $300, and the effective APR rises to about 40.6%, which is the fee's true annualized cost relative to the cash you actually received.

The remaining slice of the invoice — the gap between the advance rate and 100% — is typically released to you once your customer actually pays, minus the fee already taken, though the specific reserve-release mechanics vary by factoring company and contract and aren't modeled here.

Flat, per-period and tiered factoring fees

Flat fee: one percentage for the invoice however long it takes to pay. This is what the calculator models, and it is why a slow payer lowers the effective APR here — the same dollars are spread over more days.
Per-period fee: a rate charged for each block of time the invoice is outstanding, for example 1.5% per 15 days. Work out the total for your expected payment date (1.5% × 4 periods = 6% for 60 days) and enter that as the discount rate.
Tiered fee: a lower rate if the customer pays quickly that steps up at set points, such as 2% within 30 days and 3.5% within 60. Enter the rate for the tier you actually expect to land in.
Under per-period and tiered pricing a slow-paying customer raises the dollar fee, so run the calculation at the late end of your customer's real payment history, not the invoice terms.

How invoice factoring works

You sell an unpaid invoice to a factoring company. It pays you most of the value straight away (the advance) and holds the rest back as a reserve. Your customer then pays the factor directly, and when that payment arrives the factor releases the reserve to you minus its fee.

In recourse factoring you must buy back or replace an invoice the customer never pays, so the credit risk stays with you and the fee is usually lower. In non-recourse factoring the factor absorbs some or all of that risk — typically only for customer insolvency, as defined in the contract — and charges more for it. This calculator applies the same math to both.

The 30-day default, and when it's silently wrong

If you leave the days-to-payment field blank, the estimator assumes 30 days and marks the result as using that assumed figure rather than a number you actually confirmed. Your real customer's payment terms — net 15, net 45, net 60 — should replace that default whenever you know them, because the APR conversion is directly proportional to that day count.

An invoice amount of zero or less, a discount rate outside 0 to 100%, or an advance rate above 100% are all rejected with a specific field error rather than producing a net amount that looks plausible but is quietly meaningless.

What this estimate can't tell you

The reference conversion (rate ÷ days × 365) was checked against how the factoring industry describes its own pricing as of August 2026 — actual factor rates, advance rates, and fee structures vary by provider, your customer's credit, and your industry, and change over time.
It doesn't model recourse versus non-recourse factoring, which changes who eats a customer's non-payment risk and typically changes the price.
It doesn't account for a factor's minimum monthly volume commitment or long-term contract terms, which can matter more to total cost than the headline discount rate.
Treat any number here as a way to sanity-check a quote you already have, not as a substitute for reading the actual factoring agreement or asking an accountant to review it.

Questions people ask about Invoice Factoring Cost Estimator

What are typical invoice factoring rates?: The calculator holds no market data, and its 3% default is only an example. Industry guides commonly cite discount rates of roughly 1% to 5% per 30 days, with the rate depending on your customers' credit, your monthly volume, your industry and whether the arrangement is recourse or non-recourse. Plug in the rate from an actual quote.
Is invoice factoring a loan?: Usually not in form: you are selling the invoice rather than borrowing against it, and repayment comes from your customer rather than from you. With recourse, though, you carry the risk if the customer doesn't pay, so the cost behaves much like short-term financing. How it is treated in your accounts is a question for your accountant.
What is a factoring advance rate?: It is the percentage of the invoice's face value the factor pays you upfront, often quoted in the 80% to 90% range. The rest is held as a reserve and paid to you, less the fee, after your customer settles the invoice. In this calculator, a 90% advance on $10,000 is $9,000.
What other fees do factoring companies charge?: Factoring contracts can add application or due-diligence fees, credit-check charges, bank transfer fees, monthly minimums if your volume falls short, and termination fees for leaving early. None of these are modeled here, so add them to the discount rate as a percentage of the advance if you want a single all-in figure.
Why does the effective APR seem so much higher than the discount rate I was quoted?: Because the discount rate is a flat fee for one invoice's holding period, not an annual rate — annualizing a short holding period naturally produces a much bigger number. A 3% fee on a 30-day invoice becomes roughly 36.5% once expressed as an APR, even though nothing about the actual dollar cost changed.
What happens if I don't know exactly how many days until the invoice gets paid?: The estimator defaults to 30 days and flags the result as based on that assumption rather than a confirmed figure. If your customer's actual terms are longer or shorter, enter them directly — the APR conversion moves proportionally with that day count, so an inaccurate guess meaningfully skews the result.
Does this account for whether the factoring is recourse or non-recourse?: No. Recourse factoring, where you're on the hook if your customer doesn't pay, typically prices differently than non-recourse factoring, where the factor absorbs that risk — this estimator applies the same discount-rate math to either arrangement and doesn't distinguish between them.
Can I use this number to compare a factoring quote against a bank loan offer?: It gives you a rough, same-basis comparison point, but a real factoring contract and a real loan differ in more than headline rate — reserve holdbacks, minimum volume commitments, and recourse terms all affect true cost. Confirm the actual numbers with an accountant before choosing between the two.

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Content reviewed 2026-09-27.