Business loan interest, explained in dollars instead of jargon

Two lenders can offer you $100,000. One says the loan will cost $9,000. The other says it will cost $14,000. The cheaper-looking one may well be the more expensive, and the reverse is just as possible. The reason is not that anyone is lying; it’s that “interest” means different things in different products, and the headline figure is only the start of the story.

This guide leaves out percentages altogether on purpose. Rates change, they differ by lender and by borrower, and they hide more than they reveal. Instead, we’ll translate each way interest works into dollars you can compare.

What is interest, in one paragraph?

Interest is what a lender charges you for the use of its money, on top of paying the money back. It compensates the lender for waiting, for the risk you won’t repay, and for its own costs of funding. For a business borrower it’s a deductible expense in most cases, which is worth discussing with your accountant, though the principal you repay isn’t.

Everything else in this guide is variations on three questions: what is the interest charged on, when is it charged, and what else gets added to it.

How do the main methods of charging interest compare?

Reducing balance (the usual bank method)

Interest is worked out on whatever you still owe, usually daily, and charged monthly. Each repayment covers that month’s interest first, and the remainder reduces the principal. Next month, the balance is lower, so the interest is lower.

An illustration with invented numbers: you borrow $60,000 and repay $5,000 of principal a month for twelve months. If month one’s interest charge is $480, that’s calculated on $60,000. By month seven you owe $30,000, so the interest charge is about half of that first month, around $240. By the last month, you owe $5,000, and the charge is roughly $40. The total interest is the sum of all twelve, far less than twelve times the first month’s figure.

The takeaway: with reducing balance, paying down faster genuinely saves interest.

Flat or fixed-fee pricing

Some short-term lenders quote a single cost on the amount advanced. You borrow $60,000 and repay $66,000 across twelve months, a cost of $6,000. That fee doesn’t fall as you repay principal.

The trap is comparing it with a reducing-balance loan by the headline number. If you repay $5,000 of principal each month, your average balance across the year is only about half the original, so the same $6,000 is paid on a much smaller average amount borrowed. Put differently, a flat fee looks cheaper than it is, and the gap widens the faster you repay. Our factor rate calculator shows how this works for products priced as a multiple of the amount advanced.

Interest-only

For a set period, say the first twelve months, you pay only the interest. Your repayments are lower, and your balance doesn’t move. After that, you either start repaying principal (often with higher repayments than a standard loan, because you now have less time to clear the balance), refinance, or repay the lot in one go.

It’s useful for a project that hasn’t started earning yet, a property development, or a purchase you’ll sell. It’s costly when used just to make the monthly number look smaller. We unpack the trade-offs in interest-only business loans explained.

Capitalised and prepaid interest

Two other methods change when you pay.

• Capitalised interest is added to the loan balance instead of being paid, so next month you pay interest on the interest. Some short-term property loans use it because the borrower makes no repayments during the term. See what capitalised interest means for you.
• Prepaid interest is deducted from the amount you receive at settlement. A $100,000 loan with $9,000 of prepaid interest might put $91,000 in your account while you still owe $100,000. More in prepaid interest loans explained.

Both can be perfectly reasonable. The point is to know which one is in front of you.

Why doesn’t a “rate” tell you what you’ll pay?

A percentage per year only means something when the other details are the same: the same method, the same term, the same fees, the same repayment pattern. Comparing two quoted figures without those is like comparing two taxi quotes where one includes the tolls.

Business lending also lacks the consumer tools you may be used to. The comparison rate that appears on home loans and personal loans is a product of consumer credit law, and business loans generally fall outside it. There’s no standard figure that bundles interest and fees for you, so you need to build the comparison yourself, in dollars.

A simple, reliable method:

1. Ask for the total amount repaid over the full term, including every fee.
2. Subtract what you actually receive in your account on day one (watch for prepaid interest and deducted fees).
3. The difference is the real dollar cost of the loan.
4. Divide by the number of months to get a monthly cost, then check that your cash flow can carry the repayment pattern, not just the cost.

Our business loan repayment calculator handles the reducing-balance case, and how to calculate the true cost of a business loan walks through the full method.

Fixed or variable: what’s the practical difference?

With a variable arrangement, the lender can change its pricing as market conditions move. The Reserve Bank’s cash rate decisions are the most visible driver, though lenders also respond to their own funding costs. Variable loans usually allow extra repayments and early payout without a break fee.

With a fixed arrangement, the price is locked for the fixed term. Your repayment is predictable, which helps budgeting, but exiting early can trigger a break cost that depends on how market conditions have moved since you signed.

Neither is “safer” in the abstract. Ask yourself:

• Can my cash flow absorb a higher repayment if pricing rises? If not, fixing part of the loan may reduce risk.
• Might I repay early, sell the business or refinance? If yes, flexibility may be worth more than certainty.
• Is this a short-term bridge? For a few months, the difference is often small and the exit terms matter more.

More on this in how interest rate changes affect small business, and our glossary entry on variable rates has the short definition.

What else sits on top of the interest?

Interest is rarely the only cost. Read the letter of offer for:

• Establishment or application fees, paid upfront or added to the loan.
• Ongoing account-keeping fees, monthly or annual.
• Valuation and legal fees on property-secured loans.
• Early exit or break fees, sometimes a percentage of the balance or a fixed number of months’ interest.
• Late payment fees and default interest, which can be sharply higher than the standard charge.
• Security-related costs, such as PPSR registration, caveat lodgement and mortgage registration.

Our guide to business loan costs and fees lists them all. A loan with modest interest and heavy fees can cost more than one with higher interest and none.

Default interest deserves its own warning

If you miss a payment, many contracts switch to a higher default charge, sometimes on the entire outstanding balance rather than just the overdue amount. Over a few months of arrears, that can be a very large sum. If you can see trouble coming, ring the lender before the due date, not after. Lenders have hardship processes, and early contact makes them more flexible. The glossary entry for default interest is a short primer.

A worked comparison in dollars

Two offers for $80,000 over twelve months, both invented for illustration.

	Offer A: reducing balance	Offer B: flat fee
Amount received	$80,000	$80,000
Fees at settlement	$1,200	$0
Monthly repayment	Falls slightly each month (equal principal)	$7,333 (equal instalments)
Total interest or fee	$4,300	$8,000
Total repaid, including fees	$85,500	$88,000
Dollar cost of borrowing	$5,500	$8,000

Offer B was a simple “one fee” presentation that looked tidy and had no establishment charge. Offer A had a visible fee at the start. But A costs $2,500 less across the year, and if you repay early, the gap widens, because B’s fee is locked in. If A’s early repayments are higher and your cash flow is tight, B’s steady monthly figure might still suit you. The question is no longer “which is cheaper” but “which is cheaper for how I will actually repay”.

That is what comparing in dollars buys you.

Quick questions to ask any lender about interest

• Is interest calculated on the reducing balance or on the original amount?
• Is it charged daily, monthly or upfront?
• What is the total amount I’ll repay, including every fee?
• What happens if I repay early? Is there a break cost or a minimum term?
• Is any interest capitalised or prepaid?
• Is there a different charge if I’m late, and what triggers it?
• Does the price change during the term, and what controls that?

Our page on questions to ask a business lender before you sign extends this list.

Not sure which structure suits your cash flow? A quick enquiry lets us look at the shape of your repayments before you commit to anything.

When you’d rather someone else did the comparing

Comparing offers in dollars is the right approach, and it’s work. If you’d like a second pair of eyes, or you’ve been told no by your bank and aren’t sure what a fair alternative looks like, that’s something we do every day.

The enquiry takes about a minute, and it isn’t a credit check, so your file stays exactly as it is. We don’t pass your details to a long list of lenders. One specialist reads your situation and calls to talk through the structures that could suit it, in plain dollars. Entering your real amount, timeframe and trading history helps us suggest the right shape first time.

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