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How to use the Bank Affordability calculator
This tool shows what a bank is legally allowed to lend you, using the same affordability test the National Credit Act forces every lender to run. It is the answer to why was I declined, or why so little, worked out before you apply.
Under NCA Regulation 23A a credit provider must subtract your statutory deductions, a minimum living-expense figure from a gazetted table, and your existing debt from your gross income. What is left, your discretionary income, caps the new repayment. This tool turns that headroom into the home loan it supports. No other SA calculator shows you the living-expense table that does the damage.
Your income is not what the bank lends against. Your discretionary income is, and the minimum-expense norms and your existing debt can shrink it sharply. Clearing a car or a credit card before you apply often lifts what you can borrow more than a raise would.
What you'll need
- Your gross monthly income.
- Your existing monthly debt: every repayment a credit bureau sees, like cards, personal and car loans, and store accounts.
- The rate and term to test, to turn the affordable instalment into a loan amount.
- Your statutory deductions, PAYE and UIF, which the tool can estimate.
How to use it
Enter your gross income and your existing debt. Be thorough with the debt: the bank pulls it from the bureau, so leaving an account out only fools you.
Set the rate and term to convert the headroom into a loan. Prime is 10.5% as at June 2026, and you can tap 20, 25 or 30 years. Leave statutory deductions on Auto (SARS) for a PAYE-and-UIF estimate, or Manual to enter the exact figure from your payslip, including medical aid or retirement.
Reading your result
The headline is the most a bank may lend, the loan your discretionary income supports at the rate and term shown. Beside it sit the maximum new instalment, your monthly legal headroom, and the Regulation 23A living-expense figure the law assumes for your income.
The stacked bar shows where your income must legally go: statutory deductions, minimum living expenses, existing debt, and what is free for new credit. If you are over-committed, the tool says so plainly: a lender would see no room.
A worked example
A R45,000 gross income, R6,000 of existing debt a month, tested at 10.5% over 20 years.
The tool estimates R9,453 in PAYE and UIF and applies a R4,495 minimum living expense for that income. After those and the R6,000 of debt, R25,052 a month is free for a new bond. At 10.5% over 20 years that supports a home loan of about R2,509,227. Clear the R6,000 of debt first and the ceiling climbs by about R600,000, the loan another R6,000 a month would carry.
What it does not do
It computes the legal ceiling, not a bank's own policy, which is often stricter, and not an offer. The statutory estimate is PAYE and UIF only; your payslip may carry more. The minimum-expense norms are the 2016 gazetted table, verified in June 2026; a 2025 draft changes its scope, not its values. It is information, not a lending decision.
First-time buyer on a modest income? The First Home Finance calculator shows the subsidy you may qualify for. When you are ready, open Bank Affordability.
Money Cat is an information tool, not financial advice or a credit assessment. The NCA test here is the legal minimum; lenders may apply stricter rules. Confirm with your bank.