If your South African home loan is linked to JIBAR, the benchmark used to calculate your interest rate is changing. The JIBAR replacement will matter because JIBAR is scheduled to end after its final publication on December 31, 2026.
The transition does not mean every mortgage will automatically receive the same new rate. Here is what the change means for existing loans, interest rates, monthly payments and the steps borrowers can take before the deadline.
Why is JIBAR being replaced?
JIBAR, the Johannesburg Interbank Average Rate, is a benchmark used in financial contracts, including some South African residential mortgages.
The South African Reserve Bank and the Market Practitioners Group have been working on a replacement framework because JIBAR will no longer be published after December 31, 2026. All JIBAR tenors will cease on that date.
For borrowers, the key issue is simple:
Your loan cannot keep relying on a benchmark that is no longer available.
That means lenders need to determine how affected contracts will reference an alternative rate.
What will replace JIBAR?
The preferred successor is ZARONIA, or the South African Rand Overnight Index Average.
Unlike JIBAR, ZARONIA is based on actual unsecured overnight wholesale funding transactions in South African rand. It is published by the SARB every South African business day.
The two benchmarks therefore work differently:
JIBAR
→ Forward-looking term benchmark
ZARONIA
→ Overnight benchmark based on transaction data
The market is also developing Term ZARONIA, a forward-looking term rate based on ZARONIA-linked derivatives. FTSE Russell was selected as its administrator in 2026, but final endorsement remains subject to sufficient liquidity in the derivatives market.
Will your home loan automatically move to ZARONIA?
Not necessarily. The preferred successor does not mean that every existing mortgage will simply replace the words “JIBAR” with “ZARONIA.”
The MPG’s retail recommendations consider several possible approaches because mortgage contracts have specific requirements under South Africa’s National Credit Act.
Depending on the contract and lender, the transition could involve:
- a ZARONIA-based rate;
- a term-based ZARONIA approach where appropriate;
- another approved reference rate;
- an existing contractual fallback mechanism; or
- a negotiated amendment to the loan agreement.
The exact method depends on the individual contract and the transition framework applicable to it.
What does the JIBAR replacement mean for your interest rate?
The JIBAR replacement is not simply a matter of choosing whichever benchmark produces the lowest or highest rate.
A mortgage rate can contain several components:
Reference rate
+
Lender’s margin or spread
+
Any applicable adjustment
When a benchmark changes, the transition methodology needs to account for the difference between the old and new reference rates.
The MPG has recommended a credit adjustment spread methodology for JIBAR-to-ZARONIA transitions. Its purpose is to account for structural differences between the benchmarks and support economic equivalence.
So, a change in the benchmark does not by itself tell you whether your personal mortgage rate will rise or fall.
Could your monthly payment change?
It could.
Your monthly instalment depends on factors such as:
- the interest rate;
- outstanding loan balance;
- remaining term;
- repayment structure;
- and the way the replacement benchmark is applied.
JIBAR-linked residential mortgages typically reference 3-Month JIBAR and use monthly instalments. The MPG has specifically examined how these loans can transition while complying with the National Credit Act and protecting the economic position of borrowers and lenders.
That means the important question is not simply:
“Will my payment change?”
It is:
“How will my lender calculate my rate after JIBAR ends?”
Once that calculation is clear, you can determine what it means for the instalment on your specific loan.
What happens to existing JIBAR-linked mortgages?
Existing mortgages are a major part of the transition because many JIBAR-linked loans extend beyond the end of 2026.
The MPG’s retail-market work specifically addresses these legacy contracts, including loans that mature after JIBAR cessation.
For an existing borrower, the process may involve:
1. Reviewing the contract
The lender identifies the benchmark and any fallback language already included.
2. Selecting the transition approach
The appropriate replacement methodology is determined for the affected loan.
3. Making contractual changes if necessary
Some agreements may require amendments, notifications or other steps.
4. Applying the new rate
The replacement methodology takes effect according to the relevant contract and transition process.
The MPG has emphasized contractual remediation and preparation of legacy exposures ahead of the cessation date.
What should you check in your mortgage agreement?
If you have a JIBAR-linked loan, look for the section that explains how your interest rate is determined.
Check these five points:
- Reference rate: Does the contract specifically name JIBAR?
- Tenor: Does it refer to 3-Month JIBAR or another tenor?
- Margin: What percentage is added to the benchmark?
- Fallback: What happens if JIBAR is unavailable?
- Amendments: What does the agreement say about changing the reference rate?
You do not need to calculate the new rate yourself just to understand the transition.
The most useful information to request from your lender is the new reference rate, the applicable spread and the date the change will take effect.
When is the transition happening?
The process is already underway.
May 1, 2026
The “no new JIBAR” initiative began. With limited exceptions, market participants should no longer issue new financial contracts referencing JIBAR. New products should reference ZARONIA or another suitable rate.
Throughout 2026
Market participants are working on contractual remediation, operational preparation and transition of existing JIBAR exposures.
December 31, 2026
JIBAR is scheduled to be permanently discontinued after its final publication.
So if your mortgage is still JIBAR-linked in September 2026, there is a limited period left to understand how your lender plans to handle the change.
Does this affect every South African home loan?
No. The transition applies to contracts that reference JIBAR.
If your mortgage uses another benchmark, the end of JIBAR does not automatically change your loan.
The SARB also notes that ZARONIA will not necessarily be mandated for every situation. Other approved reference rates may be appropriate for particular contracts or exposures.
A useful first step is therefore to check your loan agreement before assuming that the transition applies to you.
What should you ask your lender?
If your agreement references JIBAR, ask for the transition details in writing.
You can use this checklist:
Reference rate
- What rate will replace JIBAR?
Timing
- When will the change take effect?
Calculation
- How will my new interest rate be calculated?
Spread
- Will my existing margin remain the same?
- Is a credit adjustment spread being applied?
Payment
- Could my monthly instalment change?
- Can you provide an example using my current balance and remaining term?
Contract
- Do I need to sign an amendment?
- What happens if my existing agreement does not contain a clear fallback provision?
These questions can help you compare the proposed calculation with the terms of your current mortgage.
What should homeowners do before JIBAR ends?
You do not need to make a decision based solely on the fact that JIBAR is ending.
Instead, focus on understanding your specific loan.
Start here:
1. Find your reference rate
Check your mortgage agreement or latest loan statement.
2. Confirm whether it is JIBAR-linked
Look specifically for the benchmark name and tenor.
3. Read the fallback clause
See what the contract says should happen if JIBAR becomes unavailable.
4. Contact your lender
Ask how the transition will apply to your agreement.
5. Check the proposed calculation
Look at the replacement rate, spread, remaining balance and expected instalment.
The JIBAR replacement is ultimately a contract-specific change within a broader market transition. Understanding how your lender will apply it is more useful than assuming every South African mortgage will move to the same rate.