Two loans. Both say "3% per annum." One costs you thousands more than the other. That's not a scam — it's just two different ways of counting the same interest, and almost nobody explains which one they're quoting. Let's fix that.
The two methods, in plain English
Flat rate (also called simple rate): the lender takes your original loan amount, multiplies it by the rate, multiplies that by the number of years — and that's your total interest, fixed on day one. It doesn't care that you've been paying the loan down every month. Month 1 and month 59, you're being charged on the full original sum.
Reducing balance (also called effective or diminishing rate): interest is charged only on the balance you still owe. Every payment shrinks the principal, so next month's interest is a little smaller. Pay more, owe less, get charged less. This is how a proper mortgage works — and how BNM wants every loan to work.
Same headline number, very different behaviour. Here's the proof.
Worked example — RM30,000 over 5 years
| Flat rate @ 3% | Reducing balance @ 3% | |
|---|---|---|
| Interest calculated on | Original RM30,000, every month | Only the balance still owed |
| Total interest over 5 yrs | RM4,500 | ~RM2,343 |
| Total repaid | RM34,500 | ~RM32,343 |
| Monthly payment | RM575 | ~RM539 |
Flat interest = RM30,000 × 3% × 5 = RM4,500, split evenly across 60 months. Reducing-balance figures computed on a standard amortisation schedule at a true 3% annual rate. Numbers rounded.
Look at the gap: same 3%, but the flat version costs nearly twice the interest. That's the whole game. The flat rate sounds identical, so it wins the shelf-appeal battle while quietly charging you more.
Effective interest rate (EIR): how to translate flat into real
The effective interest rate is the honest number — what a flat rate actually costs once you account for the fact that your balance is falling the whole time.
Rule of thumb: a flat rate is roughly 1.8× to 1.9× the effective rate on a typical multi-year loan.
- 3% flat ≈ ~5.5% effective
- 4% flat ≈ ~7.5% effective
- 5% flat ≈ ~9% effective
The concept, exactly: on a flat loan you pay interest on money you no longer have. By the final year you've repaid most of the principal, but you're still being charged as if you owe the full amount. The EIR spreads the real cost against your actual shrinking balance — which is always higher than the flat number, never lower. If someone quotes you a flat rate and calls it "the interest rate," mentally multiply by ~1.8 to know what you're really paying.
What BNM is changing on 1 January 2027 (verified)
Here's what is confirmed by Bank Negara Malaysia and Malaysian press — kept separate from analysis.
Confirmed facts:
- Personal financing: From 1 January 2027, financial service providers are prohibited from using a flat rate and/or the Rule of 78 to compute interest on personal financing. They must use fixed or floating rates on a reducing-balance basis instead.12
- The Rule of 78 is the front-loading method that gives you no interest savings for settling early. It's being scrapped for the same reason.3
- Disclosure: Lenders must show the effective interest/profit rate, total repayment, and calculation method up front — including in ads.1
- What personal-financing rules cover: personal loans and Buy Now Pay Later (BNPL). They exclude property, vehicle financing, credit cards, and revolving credit with no fixed tenure.1
- Car loans (hire purchase) — separate track: The Hire Purchase (Amendment) Bill 2025 passed the Dewan Rakyat on 8 October 2025 and also abolishes flat rate + Rule of 78 for hire purchase. Providers get an 18-month grace period from the date the amended Act is gazetted (gazette expected Q1 2026), so the real HP deadline lands around mid-2027. Replacement: EIR + reducing balance.4
- EIR caps (hire purchase): reported at 17% p.a. for tenures up to 5 years and 16% p.a. for tenures over 5 years.1
Not yet confirmed / unclear:
- Existing loans: For hire purchase, reporting says the change applies to new agreements only — existing loans keep their original terms.4 For personal financing, the published summaries do not state whether current loans are grandfathered. Treat existing personal loans as unconfirmed until BNM's own policy document is checked — don't assume your live loan converts automatically.
- Whether EIR caps also apply to personal financing (vs hire purchase only) is not clearly stated in the sources reviewed.
This is a fast-moving policy area. Verify against Bank Negara Malaysia's own published policy document before making a decision that hinges on the exact date or scope.
What this means for you — before and after the switch
After 2027, comparing loans gets genuinely easier. Every lender will have to quote the same honest number (EIR on reducing balance), so "3% here vs 3% there" will finally mean the same thing. The shelf-appeal trick dies.
Before 2027 — i.e. right now — the old rules still apply, and flat-rate offers are everywhere. Should you wait for the ban? Usually no. The ban changes how loans are quoted and calculated going forward; it won't retroactively rewrite an offer you take today, and delaying a needed purchase to chase a pricing change you can already work around by hand rarely pays. The smarter move is simply to convert every flat quote to its effective rate yourself and compare like-for-like. That's a skill the ban is about to make unnecessary — but until 1 Jan 2027, it's still on you.
Which Malaysian loans still quote flat rates today
- Personal loans — very commonly advertised as a flat rate. This is the exact product BNM is fixing first.
- Hire purchase / car loans — the classic. Malaysian car-loan adverts almost always quote a flat rate (e.g. "2.7% p.a."). By long-standing convention that flat number roughly doubles as an effective rate — so a "2.7% flat" car loan behaves like a ~5% real loan. This convention is exactly what the Hire Purchase Amendment is retiring.
- Some BNPL / instalment plans — now pulled under BNM's personal-financing framework.
Mortgages and most property financing already use reducing balance, so they're not the problem here.
Try it yourself: drop a flat-rate car offer into our car-loan calculator and it'll show you the effective rate and the real total you'll repay. Then check what you can actually afford with the eligibility calculator.