Business Loan Calculator for US Businesses

Last reviewed: 17 May 2026

Calculate US business loan repayments at SBA, conventional, and alt-lender rates. Monthly payment, total interest, and full amortisation in dollars.

Monthly business loan payment uses the standard amortisation formula: P × [r(1+r)^n] / [(1+r)^n − 1], where P is principal, r is the monthly rate (APR ÷ 12 ÷ 100), and n is total months. A $50,000 loan at 8% APR over 60 months has a $1,013.82 monthly payment.

A US business loan calculator uses the standard amortisation formula to compute monthly repayments and total interest cost at prevailing 2026 US small business lending rates. With the Federal Funds rate sitting in the 4-5% range and Prime tracking at roughly 7-8%, the all-in cost of US SMB borrowing in 2026 spans a wide arc — from 7-10% on conventional bank term loans to 15-30% APR on alternative lenders. The SBA.gov website, Federal Reserve Senior Loan Officer Opinion Survey, and NFIB Small Business Economic Trends report are the authoritative sources for current US small business lending benchmarks.

US small business borrowing in 2026 has settled into a five-product market that this calculator handles cleanly:

1. SBA-7(a) — the workhorse of US small business lending - Up to $5 million principal, 10-year working capital / 25-year real estate amortisation - Pricing: Prime + 3.0% to 6.5% (tiered by loan size); larger loans get the lower spread - Typical 2026 all-in APR: 9-12% with Prime at ~7-8% - SBA guarantee: 75% on loans above $150k, 85% on loans below $150k - Use of funds: working capital, equipment, owner-occupied real estate, business acquisition, refinance

2. SBA-504 — fixed-asset and real-estate financing - Up to $5.5 million ($5M project portion, plus the lender's first-mortgage portion can push total to $20M+) - Structure: 50% bank first mortgage, 40% CDC/SBA debenture at sub-market fixed rate, 10% borrower equity - Pricing: 504 debenture portion ~6% fixed (2026 Treasury-plus), bank first mortgage at market - 10, 20, or 25-year amortisation

3. Conventional term loan - $50k-$10M+ - Pricing 7-10% APR for established borrowers with collateral - 3-7 year typical term - Bank or credit union, often relationship-based

4. Business line of credit - Revolving, $10k-$1M typical - Prime + 1.5% to 5% on drawn balances - Often interest-only during draw period

5. Alternative lenders (OnDeck, Bluevine, Funding Circle, Kabbage, Fundbox) - $5k-$500k - 15-30% APR effective on short-term and 6-18% on medium-term - Faster decisions (24-72 hours) but materially higher cost

Worked example — SBA-7(a): A US small business takes a $100,000 SBA-7(a) loan at 10% APR over 10 years to fund a build-out. Using M = P × [r(1+r)^n] / [(1+r)^n − 1] with r = 0.10/12 = 0.008333 and n = 120, the monthly payment is $1,321.51. Total paid over 120 months = $158,581. Of that, $100,000 is principal and $58,581 is interest — about 59% of the original principal paid in interest over the term.

The personal-guarantee reality: almost every US SBA loan requires personal guarantees from owners holding 20% or more equity. Most conventional small business loans also require personal guarantees until the business has substantial standalone credit history. This means SMB borrowing in the US is, in practice, secured by the owner's home and personal assets in most cases — the calculator's monthly payment is the public number, but the personal-asset exposure is the private one.

Origination and SBA guarantee fees: conventional lenders charge 0-5% origination fees that should be added to the principal when modelling true cost. SBA-7(a) borrowers also pay an upfront guarantee fee, tiered by loan size: 0% on loans up to $1M during current SBA fee-waiver windows, 0.55% on $1M-$1.5M, 0.75% on $1.5M-$2M, and 0.85% on $2M-$5M (check current SBA fee notices, as these are revised). On a $100k SBA-7(a) the guarantee fee under the current waiver is $0; on a $2.5M loan, roughly $20,000.

For authoritative current data, the SBA.gov SOP 50 10 7 sets the underwriting and pricing rules for 7(a) and 504 loans, the Federal Reserve's H.15 release publishes Prime daily, the Senior Loan Officer Opinion Survey tracks tightening or easing in SMB credit standards quarterly, and the NFIB Small Business Economic Trends survey publishes monthly SMB borrowing-needs data. Pair this calculator with /roi-calculator/us to test whether the debt-funded project actually pays off and /cash-flow-calculator/us to confirm the monthly payment fits projected cash flow.

See the formula

See parent calculator at /business-loan-calculator for the full formula reference.

Frequently Asked Questions

How do I calculate business loan repayments?

Monthly Payment = P × [r(1+r)^n] / [(1+r)^n − 1], where P is the loan amount, r is the monthly interest rate (annual rate ÷ 12 ÷ 100), and n is the total number of monthly payments. This calculator does this automatically — just enter the loan amount, rate, and term.

What is an amortisation table?

An amortisation table shows the breakdown of every loan payment into principal (reducing the loan balance) and interest (the cost of borrowing). In early payments, most of your payment is interest. Over time, the proportion shifts toward principal. This table shows exactly how your loan balance reduces each month.

What interest rate should I use for a business loan?

In the USA, SBA 7(a) loans currently range from 6.5–9.5%. Conventional unsecured business loans: 8–25% depending on creditworthiness. In the UK, 7–15% for SME unsecured loans. In South Africa, prime rate is approximately 11.75%, with loans typically at prime + 2–5%.

Is it better to take a shorter or longer loan term?

A shorter term means higher monthly payments but less total interest paid. A longer term means lower monthly payments but significantly more total interest. Use this calculator to compare: a $50,000 loan at 8% costs $10,829 in interest over 5 years vs $18,526 over 10 years.

What is APR and how does it affect my loan cost?

APR (Annual Percentage Rate) is the true annual cost of borrowing including fees, not just the stated interest rate. Always ask lenders for the APR, not just the interest rate. A loan with a lower interest rate but high fees can have a higher APR than a loan with a slightly higher stated rate but lower fees.

How do business loan rates compare across the US, UK, and SA?

US SBA-backed loans are the cheapest at 6.5–9.5%, conventional bank loans 8–15%, online lenders 15–35%. UK SME loans range from 7–15% from high-street banks, with alternative lenders going to 25%+. South African business loans typically start at prime (around 11.75% in 2026) plus 2–5% — so 13.75–16.75% is common. Regional risk profiles and central-bank rates explain most of the gap.

What is the most common business loan mistake?

Borrowing the maximum approved rather than what the business actually needs. Approval amount is set by what you can theoretically repay, not what generates returns above the cost of the loan. Borrowing $200,000 when $80,000 would have funded the project just creates $120,000 of unnecessary interest expense (about $10,000 a year at 8%) and ties up future borrowing capacity for no benefit.

What if my interest rate is zero (a 0% deal)?

The amortisation formula divides by the interest rate, so a literal 0% would cause an error. The calculator handles 0% by switching to a simple division: monthly payment = loan amount ÷ number of months. Total interest is zero. Genuinely free loans are rare in business lending; if you see a 0% offer, check for origination fees, prepayment penalties, or balloon payments that shift the cost elsewhere.

I have my monthly payment — what should I check next?

Three tests. One: payment as a percentage of monthly revenue — under 10% is comfortable, 10–20% is manageable, above 20% is risky. Two: the project being financed must generate cash returns greater than the interest cost (otherwise borrowing destroys value). Three: stress-test the payment against a 20% revenue drop. If the business breaks at that drop, the loan is too large or the term too short.

How is a business loan different from a line of credit?

A loan is a lump-sum disbursement with fixed monthly payments over a set term — best for one-off purchases like equipment or a vehicle. A line of credit is a pool you can draw from and repay flexibly, paying interest only on what you've borrowed — better for managing cash flow gaps. Loans typically have lower interest rates; lines of credit offer flexibility at slightly higher cost.

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Methodology & sources

Rates last verified: May 2026

Read the full methodology →

Pre-fill rates are mid-range SME rates for each region: US SBA 7(a) ~7.5%, UK SME ~8.5%, SA prime + margin ~14.5%. Actual rates vary by lender, term, credit, and collateral. APR includes fees; lenders quoting headline rates may be missing fee components.

Primary sources

Rates are reviewed annually or when a region changes its headline rate. If you spot one that's out of date, email [email protected].

For information only. This calculator does not constitute financial, accounting, or tax advice. Consult a qualified professional before making business decisions.

Try these scenarios

Pre-filled examples — click any chip to load the inputs and result.

How to calculate business loan repayments

Enter loan amountTotal principal you intend to borrow.
Set the annual interest rate (APR)Pre-filled with the typical SME rate for your region — override with the actual rate you're being offered.
Set the loan termToggle between months or years, then enter the term length.
Read monthly payment and total costThe calculator shows the fixed monthly payment, total interest paid, and total cost over the full term.
Expand the amortisation scheduleClick to view the month-by-month breakdown of principal vs interest in each payment.

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Written by

James Blanckenberg

Founder, BusCalcTools

Founder of BusCalcTools and FinnCalc. Builds practical financial calculators for small business owners and freelancers across the US, UK, and South Africa.

Editorial review by: James Blanckenberg, Founder & Editor

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