The Unused Line Fee: Why Your Lender Charges You for Credit You Never Touch

Most business owners read a line-of-credit offer the way they read a credit card: if I don’t borrow, I don’t pay. On a commercial revolving line, that assumption can be wrong. Buried in the fee schedule is a line item called the unused line fee — sometimes labeled a non-use fee, commitment fee, or facility fee — and it charges you for the credit you were approved for but never touched.

It is not a scam and it is not hidden maliciously. It is a standard feature of how banks price committed credit. But it is one of the most misunderstood costs on a business line, and it is the reason a “bigger line, just in case” can be the wrong move. Here is exactly what it is, why it exists, and how to keep it from draining cash you never borrowed.

What the unused line fee actually is

When a bank approves a revolving line of credit, it makes a commitment. It promises that the money will be there when you ask for it — up to your limit, at any time, until the line matures. To keep that promise, the bank has to hold capital in reserve and cannot fully lend that same money to someone else. Bank regulators treat unfunded commitments as a real obligation that consumes capital, which is why committed credit is not free to provide even when nothing is drawn.

The unused line fee is how the lender gets paid for that standby obligation. It is typically expressed as an annual percentage applied to the average undrawn balance over a billing period — usually billed monthly or quarterly — and it is separate from the interest you pay on whatever you actually borrow.

The mechanics usually look like this:

• Interest accrues on the drawn balance — the money in your account.
• The unused line fee accrues on the undrawn balance — your limit minus what you’ve drawn.
• Together they mean a committed line has a cost floor even in a month you borrow nothing.

So on a $500,000 line with $100,000 drawn, interest hits the $100,000 and the unused line fee hits the remaining $400,000. Draw nothing all quarter, and you still owe the fee on the full $500,000.

The plain-English version: interest is rent on money you took. The unused line fee is a reservation fee on money you asked the bank to keep ready.

Why it only shows up on committed lines

Not every line of credit carries one. The distinction that matters is committed versus uncommitted (sometimes called discretionary or demand) lines.

A committed line is a binding promise — the bank must honor your draw request as long as you’re in compliance. Because that promise ties up the bank’s capital, committed lines are where you’ll most often find an unused line fee.

An uncommitted line is one the bank can decline to fund at its discretion. There’s no firm promise, so there’s often no unused fee — but there’s also no guarantee the money shows up when you need it most. That trade-off is the whole point: the fee you resent in a quiet quarter is buying you certainty in a bad one.

How much it typically costs — and why the dollar amount sneaks up on you

Unused line fees are usually a fraction of a percent per year on the undrawn amount, and your actual rate is whatever your commitment letter states — read that number, don’t assume one. The rate looks tiny next to your interest rate, which is exactly why owners wave it through at closing.

The problem isn’t the percentage. It’s the base it’s applied to. A small rate on a large idle balance, billed every quarter, compounds into real money over a year — and it’s largest precisely when your business is healthy and borrowing little. The fee punishes exactly the behavior you’d expect to be rewarded for.

Three details change the math, and all three live in your loan documents:

• The rate. Confirm the exact percentage and whether it’s annual (applied pro-rata per period) or already periodic.
• The base. Is the fee on the full undrawn amount, or only the portion above some utilization threshold? Some lenders waive the fee if you keep average usage above a stated level.
• The averaging method. A fee on your average daily undrawn balance behaves very differently from one on your period-end balance. If it’s period-end, a single draw timed near the statement date can swing the charge.

Where the real traps hide

The fee itself is honest. The traps are in how it interacts with the rest of the agreement.

1. The oversized line you were talked into

Lenders and brokers sometimes encourage a larger limit than you need — it looks generous and it grows the relationship. But every dollar of limit above what you use is a dollar generating unused line fees. A $1,000,000 line you draw $150,000 against is paying standby fees on $850,000 of air. Size the line to realistic peak need, not to the biggest number you can qualify for.

2. The fee survives even while you’re in default on a covenant

If you trip a financial covenant, your lender may freeze new draws — but the unused fee can keep accruing on the frozen availability unless the documents say otherwise. You can end up paying to reserve credit you’re no longer allowed to use. (See how a technical covenant default can restrict a performing borrower.)

3. The borrowing base shrinks your real availability but not the fee base

On an asset-based line, your true availability is capped by your borrowing base, not your stated limit. If the fee is calculated against the full commitment rather than against eligible availability, you may be paying on credit the borrowing base would never actually let you draw. Ask which number the fee uses.

4. Early termination stacks on top

Deciding the line isn’t worth the fees and closing it early can trigger a separate early termination or prepayment fee on a committed facility. Read the termination section before you assume walking away is free.

How to lower or eliminate it

The unused line fee is negotiable far more often than borrowers realize, and it’s easiest to move before you sign. Concrete levers:

• Right-size the commitment. The single most effective move. A smaller limit you use at 60–70% beats a huge limit you use at 15%.
• Ask for a utilization waiver. Many lenders will drop or reduce the fee if your average usage stays above a threshold. If you genuinely use the line, push for this.
• Negotiate the rate, not just the interest. Owners fixate on the interest spread and ignore the fee. Both are on the table, especially if you bring deposits or other business.
• Pin down the averaging method. Average-daily-balance billing is usually fairer to a borrower with lumpy usage than period-end billing.
• Reconsider the structure entirely. If you only need cash for a known, one-time purpose, a term loan with no standby fee may cost less than a committed revolver. Weigh a line of credit against a working-capital term loan.

How it fits with your other line-of-credit costs

The unused line fee rarely travels alone. A committed line can also carry an upfront or annual origination or facility fee, interest on draws, and sometimes a minimum-usage or minimum-interest charge. When you compare two offers, compare the total annual carrying cost at your realistic usage — not the headline interest rate. A line with a lower interest rate but a higher unused fee can be the more expensive line if you borrow infrequently.

The takeaway

The unused line fee is the price of a promise: the bank keeps your credit on standby, and you pay a small toll for the certainty. That toll is reasonable when you actually rely on the line. It becomes dead weight when you’re carrying a limit far larger than you use. Before you sign, find the fee in the schedule, confirm the rate, the base, and the averaging method, and size the commitment to how you’ll really borrow — not to the most impressive number on the term sheet. The cheapest unused line fee is the one you never generate because the line is the right size.

Important: MidBank is not a bank, a financial institution, or a financial advisor. We are an advocate and ISO affiliate that connects businesses to vetted third-party providers. This article is general information published on October 27, 2026, not legal, tax, or financial advice — rules and rates change, and your situation is specific to you. Confirm details with the primary sources linked above and with a qualified tax or legal professional before acting.