Unused Line Fees: The Hidden Cost of an Idle Credit Line

Most revolving lines charge a commitment fee, sometimes called an unused line fee, calculated as an annualized rate applied to the undrawn portion of the facility. The lender isn't charging you for money you've borrowed; it's charging you for holding capital in reserve so it's available the moment you draw on it. That's a legitimate cost of the optionality a line provides, but it means an oversized line you rarely touch can quietly cost more over a year than the flexibility is worth.

Ask your lender exactly how the fee is calculated. Some charge on the full committed amount minus outstanding draws, averaged daily; others use a simpler quarterly snapshot. The daily-average method is more common and generally fairer, since a brief draw doesn't erase the fee for the whole period.

A draw fee is a separate charge some lenders apply each time you actually pull money from the line, on top of the interest rate on the amount drawn. It exists to cover the lender's administrative cost of processing the advance, and it's more common on asset-based lines, where each draw might require a borrowing base certificate or collateral check before funding.

These two fees pull in opposite directions: a high unused line fee pushes you toward drawing more often to make the facility worth keeping, while a high draw fee pushes you toward drawing less often and in larger amounts. Ask for both numbers together and model how you'd actually use the line, not just the headline commitment fee a lender quotes first.

Some facilities, particularly asset-based lines, include a minimum utilization requirement: language that requires you to keep a certain amount drawn, or pay a fee calculated as if you had, whether or not your business actually needs the cash. This effectively converts an unused line fee into a penalty for using the facility conservatively, which runs against the reason most companies want a line in the first place, which is flexibility.

If a lender proposes a minimum utilization clause, ask what drove it in their underwriting. It's sometimes a sign the facility was sized larger than your actual borrowing needs to hit a minimum deal size the lender wanted, in which case a smaller line without the requirement may serve you just as well.

Get clear, written answers on each of these before you sign a revolving line agreement:

• How the unused line fee is calculated, and whether it's on the daily average balance or a quarterly snapshot.
• Whether a separate draw fee applies, and how it stacks with the unused line fee.
• Whether a minimum utilization requirement exists, and what balance it assumes if you don't hit it.
• Whether the unused line fee is waived or reduced in the first year, a common concession that quietly disappears at renewal.
• What happens to all of these fees if you reduce the committed amount partway through the term.

The right size for a line of credit is the amount that covers your realistic peak borrowing need with some cushion, not the largest amount a lender is willing to offer. A bigger commitment feels like safety, but every dollar of unused capacity is a dollar generating a fee with no offsetting benefit unless you draw on it.

Model your cash flow across a full seasonal cycle, find the largest gap between cash in and cash out, and size the line to cover that gap plus a modest buffer. If the fee on an oversized line would cost more over a year than a smaller line's occasional draw-fee exposure, the smaller line is the better deal even though it looks less impressive on paper.