Factor Rate vs. Interest Rate: What's the Real Cost of Your Business Loan?

Factor rates and interest rates are both ways of expressing the cost of borrowing, but they're calculated differently and can't be directly compared. Understanding how to translate between them is essential to making an informed borrowing decision.

What a Factor Rate Is

A factor rate (also called a buy rate) is a multiplier applied to your loan amount to determine the total repayment amount. A factor rate of 1.25 on a $40,000 advance means you repay $50,000 total — regardless of how quickly or slowly you repay.

Factor rates are used for merchant cash advances and some short-term alternative loans. They're expressed as a decimal (1.10, 1.25, 1.45) — the '1' represents the principal, and the decimal portion represents the fee. A factor rate of 1.30 means you're paying 30 cents of fee for every dollar borrowed.

What an Interest Rate Is

An interest rate (expressed as APR — Annual Percentage Rate) is the annual cost of borrowing, expressed as a percentage of the outstanding balance. Unlike a factor rate, interest accrues only on the outstanding balance — so as you repay the principal, your interest charges decrease.

This is the key structural difference: a factor rate charges a fixed fee regardless of repayment speed, while an interest rate charges less total interest the faster you repay. For a 12-month loan, APR and the annualized cost of a factor rate can be compared. For shorter repayment periods, the factor rate's annualized cost is much higher than its face value suggests.

Converting Factor Rate to APR for Comparison

To compare a factor rate to an APR: first calculate the total fee (advance amount × (factor rate - 1) = fee). Then calculate the fee as a percentage of the advance amount. Then annualize based on the repayment period.

Example: $50,000 advance, factor rate 1.30, repayment period 8 months. Fee = $50,000 × 0.30 = $15,000. Fee percentage = 30%. Annualized over 8 months: 30% × (12/8) = 45% APR. This is the apples-to-apples comparison against an interest rate product. For a product you'll repay in 4 months, the annualized cost is 90% APR — expensive, but if the 4-month return on the capital justifies it, still rational.

The Right Question Isn't APR — It's ROI

For short-term business financing, APR comparisons are often misleading because no rational borrower would hold a short-term MCA for a full year. The better metric: does the return on the capital over the actual repayment period exceed the cost of the capital over the same period?

A restaurant that borrows $50,000 at a 1.25 factor rate to fund a kitchen upgrade that generates $80,000 in additional revenue over 6 months has paid $12,500 in financing costs and earned $80,000 in incremental revenue. The 'expensive' rate was actually an excellent business decision. Run the math on your specific use case, not on theoretical annual comparisons.