Last updated 23 September 2026 · Built by Kgothatso Moleke · Prime rate 10.75% (SARB, 23 September 2026) · A guide, not a credit approval
Work out what you can realistically afford before you walk into a dealership or a bank. Enter three numbers and the calculator shows what is genuinely left each month, and roughly what that stretches to on a car or a bond.
What you have left each month
R0
After debt and living costs
Safe monthly repayment
R0
Car worth about
R0
Bond worth about
R0
How this is worked out
- What you have left is take-home pay minus debt repayments minus living costs.
- Safe monthly repayment is 70% of what is left. The other 30% stays as breathing room, because a repayment that uses every spare rand breaks the first month something goes wrong.
- Car assumes a 60-month (5-year) instalment agreement at the rate you entered, with no deposit and no balloon payment.
- Bond assumes a 240-month (20-year) loan at the rate you entered. It does not include transfer duty, bond registration, rates or levies — budget separately for those.
- A lender will run its own affordability assessment under the National Credit Act and may offer more or less than this. This is a sanity check, not a pre-approval.
About the interest rate
The calculator defaults to 10.75%, the current South African prime lending rate. The Reserve Bank raised the repo rate by 25 basis points to 7.25% on 23 September 2026, putting prime at 10.75% with effect from 25 September.
Change the rate to match what you have actually been quoted. Very few people get prime exactly. A bond is priced at prime plus or minus a margin depending on your credit record and deposit, and vehicle finance usually lands one to three percentage points above prime.
The Monetary Policy Committee meets roughly every two months. When the repo rate moves, prime moves with it by the same amount, and every variable-rate loan you hold reprices accordingly.
Why the number is lower than the bank’s
A lender works out the largest repayment you can technically service. This calculator works out the largest repayment you can service and still absorb a bad month. Those are different numbers, and the gap between them is where most repossessions live.
The 30% buffer here is deliberate. Petrol goes up. The car needs tyres. Someone gets sick. If a repayment only works when nothing goes wrong, it does not work.
What the calculator leaves out
- On a car: insurance, which is compulsory on financed vehicles and often R1,000 or more a month, plus licensing, tyres and servicing.
- On a home: transfer duty, bond registration and attorney fees up front, then rates, levies and home insurance every month afterwards.
- A deposit reduces what you borrow and usually improves the rate you are offered.
- A balloon payment on a car lowers the monthly figure but leaves a large lump sum owing at the end. Treat those offers carefully.
If the number comes back low
That is information, not a verdict. Two things move it: reducing existing debt repayments, and cutting fixed monthly costs. Both raise what is left over, and both improve how a lender reads your application.
If your existing debt already eats more than 40% of your take-home pay, work on that before applying for anything new.
This is general financial education, not advice about your circumstances. Interest rates change and lenders apply their own affordability assessments under the National Credit Act. Confirm current rates and terms before committing.