Renteplafond / woekerrente

An interest rate cap — also called an interest rate ceiling or usury limit — is a legal maximum on the interest a lender may charge a borrower. Usury is the practice of lending above that limit, or more loosely, lending at rates considered exploitative. Caps are set by statute, central bank regulation, or court-applied presumption, and breaching one usually voids the excess interest and exposes the lender to penalties.

Key takeaways

• An interest rate cap sets the highest lawful price of credit; usury is what happens when a lender exceeds it.
• Caps are expressed either as a fixed number (for example, 48% per year) or as a formula tied to a benchmark rate (for example, policy rate plus a margin).
• Modern caps increasingly apply to the annual percentage rate (APR) or total cost of credit — interest plus fees, commissions and compulsory insurance — rather than the headline interest rate alone.
• Different ceilings often apply to different institution types and loan products, with microfinance and short-term credit usually permitted higher limits than banks and mortgages.
• Evidence consistently shows caps lower advertised rates but can shrink credit supply to the riskiest borrowers and push cost into non-interest fees.

What is an interest rate cap?

An interest rate cap is a regulatory ceiling that prevents a lender from charging more than a specified rate on a loan. It is a price control applied to credit. The cap may be set by a country's parliament through a usury statute, by a central bank or financial regulator through subsidiary legislation, or by a consumer credit authority that publishes maximum rates by product category.

Caps come in three broad structural forms:

FormHow it worksTypical exampleAbsolute ceilingA fixed percentage written into lawA money-lenders act limiting interest to 48% per yearRelative or formula-linked ceilingBenchmark rate plus a fixed margin or multiplePolicy rate + 4 percentage points; repo rate + 21 percentage pointsMarket-derived ceilingPeriodically recalculated from observed average market ratesAverage rate on comparable loans in the previous quarter, multiplied by a factor

A fourth, less visible category is the de facto cap: moral suasion, licensing conditions, tender requirements or state-owned lender pricing that constrains rates without any formal ceiling in law.

Ceilings are also frequently tiered. A single jurisdiction may set one limit for commercial banks, a higher one for deposit-taking microfinance institutions, and a different one again for short-term or payday-style credit — on the reasoning that the cost of originating and servicing a small, short, unsecured loan is structurally higher per unit lent.

What is usury?

Usury has two meanings that are worth keeping separate.

In the legal sense, usury is charging interest above the statutory maximum. It is a defined, testable breach: a rate is either above or below the ceiling. Consequences vary by jurisdiction but commonly include forfeiture of the excess interest, forfeiture of all interest, unenforceability of the loan contract, regulatory fines, licence revocation, and in some systems criminal liability.

In the moral and historical sense, usury means lending at rates regarded as exploitative, or in older traditions, lending at interest at all. This is the older meaning, and it is the reason many statutes are titled "usury laws" even where they only set a numeric ceiling.

Many legal systems also recognise a presumptive rather than absolute test. Rather than banning a rate outright, the statute directs a court to presume that interest above a threshold is excessive, harsh and unconscionable, shifting the burden onto the lender to justify it. This gives courts room to reopen and rewrite loan terms case by case.

Interest rate cap vs. usury: the practical difference

Interest rate capUsuryWhat it isThe ruleThe breach of the rule (or the moral judgement behind it)Who sets itLegislature, central bank, or credit regulatorDefined by reference to the cap, or by a courtNatureProspective — governs how loans may be pricedRetrospective — assessed against a loan already madeTypical remedyN/A (compliance requirement)Excess interest voided; contract reopened; penalties

Nominal rate, effective rate, or total cost of credit?

The single most consequential detail in any cap is what the cap is measured against. Three loans can carry the same stated interest rate and very different true costs.

• Nominal / flat rate — interest calculated on the original principal for the full term, regardless of repayments made. Understates true cost on amortising loans.
• Effective interest rate — interest calculated on the declining outstanding balance.
• APR / total cost of credit — the effective rate plus arrangement fees, processing fees, commissions, compulsory insurance and any other mandatory charge, expressed as an annual rate.

Worked example

A borrower takes 10,000 over 12 equal monthly instalments at a flat rate of 3% per month.

• Interest charged: 10,000 × 3% × 12 = 3,600
• Total repaid: 13,600, in twelve instalments of 1,133.33
• Stated rate: 36% per year flat
• Effective rate on the declining balance: roughly 66% per year

Add a 2% arrangement fee deducted at disbursement and a compulsory credit-life premium, and the APR moves higher still. Under a cap written against the nominal rate, this loan sits comfortably at 36%. Under a cap written against APR, the same loan is priced at more than 60% and may be unlawful.

This is why regulators have steadily migrated from nominal-rate ceilings toward APR-based ceilings: a nominal cap invites lenders to move margin out of interest and into fees, where it is harder for borrowers to compare and harder for supervisors to police.

Why regulators impose interest rate caps

1. Consumer protection. To prevent predatory lending against borrowers with limited alternatives, poor financial literacy, or urgent liquidity needs.
2. Correcting information asymmetry. Borrowers frequently cannot compute the true cost of a quoted offer, so competition on price does not discipline the market as theory predicts.
3. Affordability of credit. To lower the cost of borrowing for households and small businesses, particularly where policymakers judge lending spreads to be excessive relative to the cost of funds.
4. Political economy. Caps are visible, easily legislated, and popular. They are among the most common responses to public anger about credit costs.
5. Religious and cultural prohibition. In systems influenced by prohibitions on riba, interest itself is impermissible, and profit-sharing or mark-up structures are used instead of interest-bearing debt.

Interest rate ceilings are far from a niche instrument. World Bank research identified at least 76 countries, together representing over 80% of global GDP, applying some form of restriction on lending rates — spread across every region and income group, not concentrated in developing markets.

The evidence on unintended consequences

The empirical literature on caps is unusually consistent, and it points in the same direction across very different markets.

Credit rationing at the riskiest end. When the ceiling sits below the rate a lender needs to cover its cost of funds, operating cost, expected loss and capital charge for a given borrower segment, the rational response is not to lend more cheaply — it is to stop lending to that segment. The borrowers priced out are the ones the cap was written to protect.

Migration of margin into fees. Where the cap binds only the interest component, lenders restructure pricing toward arrangement fees, insurance commissions, monthly service charges and penalty income. Studies of capped markets have found this shift to be persistent — pricing structures often do not revert to interest-led even after a cap is lifted.

Reduced transparency. Fee-heavy pricing is harder to compare across lenders than a single quoted rate, which weakens exactly the price competition the cap was meant to substitute for.

Growth of informal lending. Demand for credit does not disappear when supply is constrained. It moves toward unlicensed lenders operating outside any consumer protection framework at all — where rates are higher, disclosure is absent and collection practices are unregulated.

Consolidation and reduced outreach. Smaller and rural-focused institutions, which carry the highest cost per loan, are the first to become unviable. Branch density and the number of licensed providers tend to fall.

None of this makes caps universally harmful. Narrowly targeted caps — on payday-style products, on penalty interest, or on specific abusive charge types — have produced measurable reductions in predatory pricing without collapsing credit supply. The design of the cap matters more than its existence.

Interest rate caps and usury laws around the world

Rules change frequently. The examples below illustrate the range of approaches rather than serving as current legal guidance.

West Africa (WAEMU/UEMOA). The Central Bank of West African States sets a union-wide usury rate applied to the APR. From 1 June 2026 the ceiling stands at 14% per year for banks and 24% per year for credit institutions, microfinance institutions and other lenders — reduced from 15% and 27% respectively. Exceeding the threshold exposes the institution to sanction by the regional banking commission.

Zambia. The long-standing Money-Lenders Act creates a presumption that interest above 48% per year is excessive and the transaction harsh and unconscionable, leaving courts to reopen such agreements. The Bank of Zambia separately imposed effective-rate ceilings on non-bank financial institutions from January 2013 — 42% for microfinance service providers and 30% for other NBFIs — before removing them in 2015. Research on that episode found bound lenders sharply reduced loan volumes and permanently shifted income from interest into fees.

Kenya. A cap limiting bank lending rates to 4 percentage points above the Central Bank Rate ran from September 2016 until its repeal in November 2019, after which the market moved to a risk-based credit pricing framework supervised by the Central Bank of Kenya.

South Africa. The National Credit Act sets formula-based ceilings per credit category, each referenced to the Reserve Bank repo rate — separate maxima for mortgages, credit facilities, unsecured credit, developmental credit and short-term transactions — alongside caps on initiation and service fees and the in duplum rule limiting accumulated arrears charges.

Continental Europe. France and Italy operate market-derived ceilings, recalculated periodically from observed average rates on comparable credit and published by category. Germany applies a court-developed doctrine of Sittenwidrigkeit, treating a rate roughly double the market average as immoral and the contract void.

United States. Usury limits are set at state level and vary widely, complicated by federal preemption rules that allow nationally chartered banks to export their home state's limit. The federal Military Lending Act separately caps most consumer credit to servicemembers and their dependants at a 36% military APR.

Usury in history

Restrictions on interest predate modern banking by millennia. The Code of Hammurabi set maximum rates on grain and silver loans. Roman law fixed a legal maximum and periodically suspended interest altogether during debt crises. Medieval canon law in Christian Europe prohibited lending at interest outright, a position that softened gradually through the distinction between illicit usura and licit compensation for risk and lost opportunity. Jewish law distinguished lending within and outside the community. Islamic jurisprudence prohibits riba — the guaranteed increase on a loan of money — which underpins modern Islamic finance structures such as murabaha mark-up sale and mudaraba profit-sharing, designed to earn return through trade and equity participation rather than interest.

The through-line is that societies have almost always regarded the price of credit as a moral question and not purely a market one. Contemporary usury statutes are the direct descendants of that view.

Compliance obligations for lenders

Operating under a cap creates concrete requirements that go well beyond setting a rate correctly at origination:

• Correct measurement basis. Establish whether the ceiling applies to the nominal rate, effective rate, or full APR, and compute the compliance figure the way the regulator computes it.
• Full inclusion of charges. Where the cap is APR-based, arrangement fees, processing charges, compulsory insurance and any other mandatory cost belong inside the calculation.
• Product-level and entity-level testing. Tiered caps mean a rate that is lawful for a microfinance licence may be unlawful for a bank, and lawful on a short-term product but not a term loan.
• Point-in-time capture. Under formula-linked caps, the applicable ceiling is usually the one in force on the date the agreement was concluded, so the benchmark and margin must be recorded on the loan file.
• Penalty and default interest. Many regimes cap default interest separately, prohibit its capitalisation, or limit total accrued arrears charges to the outstanding principal.
• Disclosure. Cap regimes almost always sit alongside mandatory pre-contract disclosure of the total cost of credit in a prescribed format.
• Re-testing on restructure. Rescheduled, refinanced and topped-up loans typically need to be tested against the ceiling again, at the terms then in force.

Alternatives to interest rate caps

Policymakers seeking lower borrowing costs without the supply effects of a hard ceiling generally reach for some combination of:

• Mandatory APR disclosure in a standardised format, so borrowers can compare offers on a single comparable figure
• Credit information sharing through credit bureaux, which lowers the risk premium by reducing information asymmetry
• Movable collateral registries, allowing borrowers to pledge assets other than land and secure lower-priced credit
• Competition and market entry policy, including licensing digital and non-bank providers to compete on price
• Conduct regulation targeting specific abuses — rollover restrictions, affordability assessment duties, collections rules — rather than the price itself
• Payment system reform to reduce the cost of disbursement and collection, which flows directly into the operating cost component of the lending rate

Frequently asked questions

Is an interest rate cap the same as a usury law? In practice they usually describe the same instrument. "Interest rate cap" is the regulatory framing; "usury law" is the legal-historical framing, and usury statutes typically operate by setting a cap.

Does a cap apply to fees as well as interest? It depends entirely on how the cap is drafted. APR-based caps include mandatory fees and charges. Nominal-rate caps generally do not, which is why fee-based pricing tends to expand under them.

What happens if a lender charges above the cap? Common consequences are voiding of the excess interest, voiding of all interest, unenforceability of the agreement, regulatory penalties, licence action and — in some jurisdictions — criminal exposure. Under presumptive statutes, the court may reopen the agreement and substitute terms it considers fair.

Do interest rate caps make credit cheaper? They reliably reduce the advertised rate for borrowers who still receive loans. Whether they reduce the total cost of credit, and for whom, depends on whether fees are captured by the cap and whether the affected borrowers retain access to formal credit at all.

Why are microfinance institutions usually allowed higher ceilings than banks? Because the cost of delivering a small, short, unsecured loan — origination, field monitoring, collections, rural operations — is far higher per unit lent than the cost of delivering a large secured loan. A ceiling set at bank economics would make small-balance lending structurally unviable.

Are caps fixed or do they move? Both. Absolute ceilings stay put until amended. Formula-linked and market-derived ceilings move as the underlying benchmark or observed market average moves, often on a quarterly or annual recalculation cycle.