Financial planning · South Africa
Should You Pay Off Your Home Loan or Invest the Extra Money?
Paying down a home loan reduces interest on the amount repaid. Investing the money instead is financially preferable only if its return after costs and tax adequately compensates you for keeping the debt and accepting investment risk. Compare the same cash amount, over the same period, with the same ongoing household payments. Then assess access to cash and the consequences of a poor outcome.
A high loan rate, short investment horizon or fragile cash flow can favour repayment. Dependable income, a long horizon and sufficient reserves can support investing some of the money. The decision need not be all or nothing.
In this article
Start with the borrowing you actually have
Use the rate on your own loan, not a headline prime rate. Check whether it is fixed or variable, how additional payments are applied, and whether the bank reduces the instalment or shortens the remaining term. Standard Bank's repayment guidance explains that extra payments can reduce interest and bring settlement forward; the precise result depends on the agreement and subsequent payments. Standard Bank: Paying your bond
The interest saving changes if the loan rate changes. Calling it a guaranteed long-term investment return can conceal that distinction. At a fixed rate and under a stated repayment schedule, the avoided interest is calculable. A variable-rate loan needs more than one rate scenario.
This article's examples concern a private home loan with no tax deduction for its interest. A rental or business-related borrowing needs a separate after-tax calculation. SARS allows qualifying expenses incurred in producing rental income, including bond interest, while excluding private and capital expenses. The full instalment is not the same as deductible interest, and the purpose of borrowing matters. SARS: Tax on rental income
Compare equal cash flows
Suppose a household owes R2 million with twenty years remaining. The assumed rate is 10% a year, compounded monthly, with monthly payments of approximately R19,300. It has R200,000 available after keeping an adequate separate cash reserve.
One option pays the R200,000 into the loan immediately and keeps the original monthly payment. The other invests R200,000 and continues the same loan payment. The home has the same value in both cases and therefore cancels out of the comparison. There are no fees for the additional loan payment in this illustration.
After ten years, the original loan balance is approximately R1,460,486. The prepaid balance is approximately R919,078. Repayment has therefore improved net worth by R541,408 relative to leaving the loan unchanged. That is the difference between the two remaining debts, not cash sitting in a separate account.
The investment has to exceed that debt difference to produce more net wealth:
| Assumed investment return after costs and tax | Investment after ten years | Investing advantage versus the R541,408 debt reduction |
|---|---|---|
| 7% a year, compounded monthly | R401,932 | Minus R139,476 |
| 10% a year, compounded monthly | R541,408 | R0 |
| 13% a year, compounded monthly | R728,747 | Plus R187,338 |
These are constant hypothetical net returns, not forecasts or descriptions of a fund. All rates in this table use the same nominal annual rate divided by twelve and monthly compounding. A quoted effective annual investment return would need conversion before comparison. Actual investments have varying returns and tax timing, and can lose value.
The comparison would be unfair if repayment released a lower instalment and that monthly saving simply disappeared from the model. In that case, include what happens to each saved payment. Spending it improves current consumption; investing it builds an asset. They are different outcomes.
To explore the repayment side of this decision, use the Debt Repayment Calculator to see how extra monthly payments could affect interest and repayment time. It models debt repayments under stated assumptions; it does not compare investment returns.
A gross return is not the hurdle
For a simple one-year interest comparison, assume the loan costs 10%, every rand of investment interest is taxed at 39%, any applicable interest exemption has already been used, and there are no investment fees. Gross interest of approximately 16.39% is needed to leave 10% after that tax: 10% divided by 61%.
At 8% or 12% borrowing costs, the corresponding hypothetical gross-interest hurdles are approximately 13.11% and 19.67%. These are arithmetic illustrations using an assumed marginal tax rate. They do not describe available deposit rates or the tax treatment of equity returns.
A share portfolio can generate dividends and deferred capital gains with different tax treatment. A tax-free account or retirement contribution introduces its own contribution, access and tax rules. Do not force those into a single annual interest-tax formula. Compare the actual investment structure and the household cash flows, including any genuine tax benefit and its timing.
Preserve cash you may need under pressure
Extra money in an access bond can be useful, but access is contractual. Standard Bank's AccessBond description distinguishes settings that make additional funds available from those reducing instalments, and states that the facility is deactivated if payments are missed. That is one provider's arrangement, not a rule for every bank. Verify your own facility, restrictions and reapplication requirements. Standard Bank: AccessBond
This matters because the moment you most need cash may coincide with weaker earnings or missed payments. A lower loan balance and an unconditional cash reserve are not interchangeable. Keep enough readily accessible money for essential expenses and known commitments before allocating every spare rand to either repayment or a long-term investment.
Also distinguish making an extra payment from settling and cancelling the bond. Ask the lender for written settlement figures, notice requirements and applicable charges before closing the facility. Do not assume that the absence of an extra-payment fee means cancellation is free or that an existing facility will remain available after settlement.
What would justify investing instead?
The strongest case is a long horizon, manageable debt, stable income, adequate liquidity and an investment exposure the household needs. Directing everything into the home can leave wealth geographically concentrated and illiquid. Building diversified financial assets may have value even when it accepts a less certain short-term outcome.
That is still an investment financed alongside debt. Test a market loss and an interruption to earnings at the same time. If a R200,000 investment falls to R140,000 when cash is needed, the loan does not fall with it. The household must be able to keep servicing the debt without being forced to sell the investment at an inconvenient time.
Conversely, the strongest case for repayment is not that shares are bad. It is that reducing a known commitment may be more useful than seeking an uncertain return, especially before retirement or when earnings are volatile. The avoided interest can remain attractive without any prediction about next year's market.
Turn the comparison into a workable decision
Obtain the loan rate, remaining term, current instalment, access rules and any settlement costs. Separate emergency cash and foreseeable spending. Then compare repayment, investment and a split allocation under consistent assumptions. Include a lower-return investment case and a higher-rate loan case if the borrowing is variable.
Record what would change the decision: refinancing, a new income source, an approaching retirement date, a depleted reserve or a change in the investment goal. Revisit the allocation when those facts change. There is no need to re-run a long-term decision after every market headline.
For the broader balance sheet, read household concentration risk. The lump-sum investing question addresses a separate choice once money has been allocated to investment. A Financial Clarity Review can help when debt, retirement, property and portfolio decisions need to be reconciled.
Sources and calculation basis
Provider and SARS pages were accessed on 6 September 2026. Provider terms are examples, not recommendations or a substitute for your agreement. All loan amounts, rates, investment outcomes and tax assumptions above are hypothetical. The monthly loan calculation remains available under technical data; the tax-hurdle example is explained above. The model excludes changing rates, transaction costs and an actual investment tax calculation by using explicitly assumed net investment returns.
General education only. The appropriate choice depends on actual loan terms, liquidity, tax, investment risk and the household's objectives.
Download home loan repayment or investing (Excel)
Inspect the fixed worked-example records in Excel, with readable headings and filters. The workbook preserves the article’s calculation data; it is not a personal planning calculator.