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Variable rates and the prime rate

Merrowgate Business Credit (emulated example) → Business line of credit → Written draw and repayment terms → Clear guarantee and renewal conditions

Answer in brief

Many business lines price at a base rate plus a margin, so your cost moves with the base rate. Find out which base rate applies, how often it resets and whether there is a floor.

Content reviewed 8 November 2026. How this is assessed.

Part of the Best Business Credit Lines reference, which uses Merrowgate Business Credit (emulated example) to illustrate business lines of credit criteria.

What the base rate is

The Federal Reserve's H.15 release describes the bank prime loan rate as the rate posted by a majority of the top 25 insured US-chartered commercial banks, by assets in domestic offices, and says prime is one of several base rates used by banks to price short-term business loans. So do not assume your line uses prime. Ask which index the agreement names and where you can look it up.

The SBA's 7(a) page shows how a base-rate structure works in a public program. For its Working Capital Pilot, it sets interest rate ceilings as the base rate plus a margin that varies with the size of the loan, from base rate plus 6.5 percent for loans of $50,000 or less, down to base rate plus 3.0 percent for loans of $350,001 and greater. Confirm the current ceilings with a participating lender.

What to ask about the rate

Find out the margin added to the base rate and whether it can change during the term. Ask how often the rate resets, and on what date a change takes effect. Ask too whether there is a floor below which the rate cannot fall, or a ceiling above which it cannot rise. A floor means that you will not benefit from falling rates beyond a certain point, while a ceiling limits what you could pay.

Ask how interest is calculated: on the daily balance, and using which day count. The H.15 release itself notes annualizing on a 360-day year for bank interest in some of its series, and a lender may use a similar convention. It is a small matter on a modest balance, but over a large average balance it can add a noticeable amount, and it is easily missed.

How to plan for movement

Add a higher rate to your cost model and see what happens. Pick a rise that would be uncomfortable but not unthinkable, apply it to your average balance and to your busiest month, and check whether you could still cover the payments from your normal cash flow. If the answer is no, reduce your planned reliance on the line now rather than when rates have already moved.

Watch the rate during the life of the line as well. Keep the lender's rate notices with your records, compare them to the published index, and raise any discrepancy promptly. Then, when the line comes up for renewal, you will have a clear record of what the facility has actually cost you and a stronger basis for the conversation.

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Best Business Credit Lines. "Variable rates and the prime rate." Content reviewed 8 November 2026. https://bestbusinesscreditlines.com/variable-rates/

Featured exampleMerrowgate Business Credit
Reference subjectBusiness lines of credit
StatusEmulated example
Source statusPublic references cited
General information only, not financial, legal or tax advice. Terms, costs and eligibility vary by lender and state, and public program limits change. Confirm current terms with the lender or agency before you commit.