Invoice Factoring Cost & APR Calculator
Enter the invoice amount, advance rate, fee schedule, payment timing, and other charges to estimate the advance, reserve settlement, net proceeds, and annualized cost.
Estimated APR-equivalent cost0.29%
- Upfront advance
- $8,500.00
- Reserve initially held
- $1,500.00
- Factoring fee
- $300.00
- Total factoring cost
- $300.00
- Reserve settlement
- $1,200.00
- Total net proceeds
- $9,700.00
- Cost as a percentage of invoice
- 0.03%
- Cash-flow timeline
- $8,500 advanced now; $1,200 reserve released after 45 days.
APR-equivalent cost is a simple annualized comparison based on the advance, total cost, and payment days.
The estimate assumes the invoice is paid in full on the entered day and excludes disputes, chargebacks, dilution, and late-payment charges unless entered as additional fees.
How to use this calculator
- Enter the face amount of the invoice or batch of invoices.
- Set the advance rate and the factoring fee rate from the proposal or contract.
- Choose whether the fee is flat, prorated by 30-day periods, or charged for each 30-day period started.
- Enter the expected customer payment timing and any extra charges, then compare the total cost and APR-equivalent rate.
How invoice factoring cost is calculated
Invoice factoring usually has two cash movements. The factor advances part of the invoice now, then releases any remaining reserve after the customer pays, net of fees. This calculator treats the quoted factoring rate as a charge against the invoice amount and changes the fee multiplier based on how the contract bills time.
The formulas are:
A = I * (a / 100)
R = I - A
F = I * (f / 100) * m
C = F + X
S = R - C
N = I - C
APR equivalent = (C / A) * (365 / d)
- I is the invoice amount.
- a is the advance rate, and A is the upfront advance.
- R is the reserve initially held by the factor.
- f is the factoring fee rate, and m is the fee multiplier.
- X is additional fees, C is total cost, S is reserve settlement, and N is total net proceeds.
- d is the number of days until the customer pays.
For a flat fee, the multiplier is 1. For a prorated 30-day fee, it is days divided by 30. For a fee charged for each 30-day period or part of one, it is the next whole 30-day period, so 31 days counts as two periods.
What moves the result most
The advance rate affects cash timing more than total cost: a higher advance gives more money now and leaves less reserve to absorb fees later. The factoring fee rate, extra charges, and payment delay drive the dollar cost. A small fee can still annualize to a high APR-equivalent rate when the invoice pays quickly because the cost is measured against the advance over a short period.
Billing basis can matter as much as the quoted rate. A 3% fee prorated for 45 days is a 4.5% invoice cost before other fees. The same 3% fee charged for each 30-day period started is 6% at 45 days because the second period is counted in full.
What this calculator leaves out
The APR-equivalent output is a simple annualized comparison, not a legally disclosed APR and not a statement that factoring is a loan. It assumes the invoice is paid in full on the entered day and that the chosen fee schedule matches the contract. It does not model recourse risk, non-recourse pricing, chargebacks, customer disputes, dilution, late-payment penalties, unused-line fees, minimum-volume commitments, collection costs, or when the factor deducts fees from the advance instead of the reserve.
Worked example
Suppose a business factors a $10,000 invoice with an 85% advance rate, a flat 3% factoring fee, no additional fees, and customer payment in 45 days. The upfront advance is $8,500 and the reserve initially held is $1,500.
The factoring fee is $10,000 * 3%, or $300. Total cost is $300, so the reserve settlement is $1,500 - $300 = $1,200. Total net proceeds are $9,700, the cost is 3% of the invoice, and the APR-equivalent cost is about 28.63% because $300 is annualized against a $8,500 advance over 45 days.
Common questions
How is an invoice factoring fee calculated?
The fee is usually the invoice amount multiplied by the quoted factoring rate, then adjusted for the fee period. A flat fee uses one period, a prorated 30-day fee uses days divided by 30, and a started-period fee rounds up to the next 30-day block.
What is the difference between the advance and the reserve?
The advance is the cash paid to the business before the customer pays the invoice. The reserve is the remaining invoice value held by the factor until customer payment, often used to cover the factoring fee and other charges before any balance is released.
What happens to the reserve when the customer pays?
After the customer pays, the factor settles the reserve by subtracting the factoring fee and other charges. If fees are smaller than the reserve, the business receives the remaining reserve; if fees exceed the reserve, the business may owe the difference.
How do payment delays increase factoring costs?
Payment delays increase cost when the fee is charged by time period. Under prorated billing, each extra day adds a proportional cost; under whole-period billing, crossing a 30-day boundary can add a full additional period.
How can I convert a factoring rate into an APR-equivalent rate?
Divide the total factoring cost by the upfront advance, then multiply by 365 divided by the number of days outstanding. This gives a simple annualized comparison, but it is not the same as a statutory APR disclosure.
Which additional factoring fees should I include?
Include charges that affect the economics of the transaction, such as wire fees, processing fees, due-diligence fees, minimum-volume fees, unused-line fees, and any charge that is deducted from proceeds or billed separately. Leave out fees only when you are sure they do not apply to the invoice being modeled.