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NZ business loan interest cost calculator.

Slide the amount, term, and indicative rate to see total interest paid across the life of the loan. The figure that reveals which deal is actually cheaper.

Last reviewed 27 April 2026

Indicative repayment

Weekly

Disclaimer

$537/week

$2,327 /month $39,610 total interest
$100,000
$5,000 $500,000
5 years
6 months 5 years
14.00% p.a.
8% (secured) 30% (unsecured)

Indicative only. Not a quote or offer of credit. Actual rates, fees, and repayments depend on the business profile and the lender's decision.

Educational

Indicative only. Why we say this

Why total interest matters

The cost of credit is bigger than the monthly repayment.

The most common framing for borrowing decisions is "what does it cost per month?" because the monthly figure determines the cash-flow impact. The total interest figure tells a different and equally important story: what is the cost of using this lender's money for the life of the loan?

On a $100,000 5-year loan, a 6-percentage-point rate difference (8% vs 14%) translates to roughly $18,000 in total interest. That is the figure most worth comparing when evaluating two offers, because monthly cost can be optically similar while total cost diverges materially.

Term vs rate trade-off

Shorter terms compound the rate savings.

The total interest figure is the cleanest way to evaluate the term-vs-rate trade-off. A 3-year secured loan at 9% vs a 7-year unsecured loan at 16% produce similar monthly costs (roughly $1,400 to $1,500 on $50K), but the 3-year secured option pays roughly $7,250 in total interest while the 7-year unsecured pays roughly $35,000. The 7-year option costs nearly 5x more across the life of the loan.

The trade-off is the monthly capacity. Where cash flow tolerates the higher monthly, the shorter term materially cuts total cost. The interest cost calculator surfaces this clearly.

At a glance

Indicative total interest on a $100,000 NZ business loan.

The figures below show total interest paid across the loan term at the indicative rate shown. Total interest excludes establishment fees and any monthly service fees.

Term 8% (secured) 14% (unsecured mid) 20% (short-term high)
2 years ~$8,500 ~$15,200 ~$22,200
3 years ~$12,800 ~$23,200 ~$33,800
5 years ~$21,700 ~$39,500 ~$59,000
7 years ~$31,200 ~$57,300 ~$86,300
10 years ~$45,600 ~$86,000 ~$131,800

FAQ

Interest cost calculator, NZ business questions

What is total interest cost on a NZ business loan?

Total interest cost is the cumulative interest paid across the life of the loan, calculated as the sum of all repayments minus the original principal. On a $100,000 loan at indicative 14% across 5 years, total interest is approximately $39,500. The interest cost is the second figure (alongside the monthly repayment) most worth understanding before signing.

How does the term affect total interest?

A longer term reduces the monthly cost but increases total interest paid because each dollar of principal accrues interest for longer. On the same $100,000 at 14%, total interest across 3 years is around $23,200; across 5 years it is around $39,500; across 7 years it is around $57,300. Doubling the term roughly doubles the interest paid.

How does the rate affect total interest?

On a 5-year, $100,000 loan, total interest at 8% is around $21,700; at 14% it is around $39,500; at 20% it is around $59,000. The rate-to-interest relationship is roughly linear at any single term length: each percentage-point of rate adds roughly $3,000 in total interest on a 5-year, $100,000 loan.

Why is total interest important if monthly cost fits the budget?

Two loans with similar monthly cost can have very different total interest figures. A $100K loan at 12% across 5 years and a $100K loan at 8% across 7 years produce similar monthly costs but the 5-year loan saves roughly $5,000 in total interest. Looking at total interest reveals which option is actually cheaper across the life of the loan.

Can I reduce total interest paid?

The strongest levers are choosing a shorter term where cash flow allows, securing the loan to access lower rates, refinancing if rates drop, and making extra repayments where the contract allows them at no break cost. Each lever compounds; combining a shorter term with a secured rate often saves materially more than either alone.

How do fees affect total cost?

Establishment fees (typically $200 to $1,500 alternative lenders, $500 to $5,000 major banks), monthly service fees ($0 to $40), and any break costs sit on top of the interest figure shown by the calculator. The total cost of credit across the life of the loan is interest plus fees; the calculator handles the interest portion only.

What is the relationship between weekly and total interest?

Weekly repayment versus monthly repayment on the same nominal annual rate produces a slightly lower total interest figure because principal pays down faster. The savings are small on short loans (under 2 years) and material on longer ones (4 to 5 years). On a $100,000 5-year loan at 12%, weekly repayment typically saves around $400 to $700 against monthly.

Are loan repayments tax-deductible?

The interest portion of business loan repayments is generally deductible against business income, subject to the accountant's confirmation, where the loan is used for business purposes. Principal repayments are not deductible. The calculator shows total interest separately to support this distinction; the accountant typically reconciles the deductible portion annually.

Disclaimer

Indicative content only. Not personalised financial advice.

A business loan is a commitment that runs for months or years, and repayments come out of the same operating cash flow as everything else. Before committing, it is worth modelling the weekly and monthly cost against the business's working-capital position, which is what this site is built to help with. Borrowing at a level that stays comfortable through a quiet quarter, not just a strong one, is widely regarded as the safer frame.

What this site is

A calculator and information tool. Not a lender, not a broker, not a registered financial adviser. Nothing here is personalised financial advice.

What the figures show

Modelled estimates based on the inputs you enter. Not a quote. Not an offer of credit. Not a guarantee of approval, rate, or fees.

What the lender decides

Final rates, fees, and approval are set by the lender after a CCCFA-appropriate assessment of the applicant's circumstances and credit decision.

Commercial disclosure

Businessloans.org.nz earns a commission from Prospa when a visitor applies through this site and their application is approved. The commission is paid by Prospa, not by the borrower, and it does not influence the rate Prospa offers. Full disclosure on the partner page.

Tax, GST, and accountant framing

Tax-treatment statements (GST claim timing, interest deductibility, depreciation rates) are general in nature and subject to your accountant's confirmation on the specific business position. For material amounts, professional advice from a registered financial adviser or chartered accountant is widely regarded as the safer frame.

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Important information

About this site, the figures, and your protections.

Last reviewed 5 May 2026.

1. What this site is

Businessloans.org.nz is a New Zealand education site and a free repayment calculator. It is not a lender, not a broker, and not a registered financial adviser. We do not arrange credit, hold client money, or provide regulated financial advice as defined under the Financial Markets Conduct Act 2013 Part 6 or the Financial Services Legislation Amendment Act 2019. Nothing on this site is personalised financial advice.

2. The calculator and figures

All numbers shown by the calculator, in worked examples, and across the site are indicative only and modelled from the inputs entered. The figures are not a quote, not an offer of credit, and not a guarantee of the rate, fees, term, or approval available to any specific business. Final pricing, fees, and approval are set by the lender after the lender's own credit assessment.

3. General information, not advice

Content on this site is general information (class information). It does not take into account the financial situation, objectives, or needs of any particular business or person. Before making a borrowing decision, professional advice from a licensed Financial Advice Provider, a chartered accountant, or a solicitor is widely regarded as the safer frame, particularly where amounts are material or the borrowing involves a personal guarantee.

4. Commercial relationship with Prospa

When a calculator user clicks "see if you qualify", the application hands off to Prospa, our New Zealand SME finance partner. Businessloans.org.nz earns a referral commission from Prospa when a referred application converts to a funded loan. The commission is paid by Prospa, not by the borrower, and does not change the rate, fees, or terms Prospa offers the business. We do not claim Prospa is the cheapest or best lender for every applicant. Full disclosure is on our partner page.

5. Tax, GST, and accountant framing

Tax-treatment statements (GST claim timing, interest deductibility, depreciation rates) on this site are general in nature and subject to confirmation by your accountant on the specific business position. For material amounts, professional tax advice from a chartered accountant is widely regarded as the safer frame. Inland Revenue is the primary source for any specific NZ tax-treatment question.

6. Privacy and personal information

Consistent with the Privacy Act 2020, we do not run lead-capture forms on this site. Calculator inputs stay in the browser and are not transmitted to a server we control. We use Google Analytics 4 for aggregate, non-personal traffic data only. When a visitor clicks through to Prospa they leave our site, and Prospa's privacy policy applies. The Credit Contracts and Consumer Finance Act 2003 (CCCFA) framework applies at the lender level where a sole trader's borrowing is wholly or predominantly for personal use, or where a personal guarantor is involved.

7. Fair dealing posture

This site operates under the fair-dealing requirements of the Financial Markets Conduct Act 2013 Part 2 and the Fair Trading Act 1986. We avoid misleading or deceptive conduct, false representations, and unsubstantiated claims. Numeric or regulatory claims are hedged or sourced to a primary New Zealand authority (NZTA, MBIE, Inland Revenue, Reserve Bank of New Zealand, Stats NZ, Commerce Commission, Financial Markets Authority).

8. Limitation of liability and governing law

To the maximum extent permitted by New Zealand law, Businessloans.org.nz, its operators, and its contributors are not liable for any loss or damage (direct, indirect, consequential, or otherwise) arising from use of the site or reliance on its content, indicative figures, or third-party information. These terms are governed by the laws of New Zealand. Any disputes are to be resolved in New Zealand courts.

Long form: terms, privacy, footer disclaimer.