Merchant Discount Rate: What It Is and What You Actually Pay

The merchant discount rate is the fee a merchant pays each time a customer completes a card transaction at their business. It is expressed as a percentage of the transaction value and is deducted automatically before the net amount is settled into the merchant's account. Some providers also add a fixed per-transaction amount on top of the percentage.

For example, if the MDR is 2.7% plus USD 0.50 and a customer pays SGD 100, the merchant receives approximately SGD 100 minus the equivalent of 2.7% plus USD 0.50 — rather than the full SGD 100. The phrase "discount" refers to this automatic deduction from the sale amount, not a promotional reduction in price.

The MDR applies to credit cards, debit cards, and digital wallets like Apple Pay and Google Pay that route transactions through card networks. Local real-time payment methods such as PayNow do not use the same MDR structure, which is one reason some merchants encourage customers to use them for lower-cost transactions. The rate you pay depends on your payment provider, the card network involved, whether the card was issued domestically or abroad, and the pricing model your provider uses.

The merchant discount rate is not a single charge — it is a blended cost made up of three distinct components that flow through the payment chain.

Interchange fee. This is the largest portion of the MDR and is set by the card networks (Visa, Mastercard, Amex, JCB, UnionPay). It is paid to the card-issuing bank as compensation for extending credit and managing fraud risk. Interchange rates vary by card type, transaction category and geography, and merchants typically have no direct control over them. Because interchange is set by the networks, every acquirer or payment provider who processes the same card type pays the same underlying interchange cost.

Scheme or network fee. On top of interchange, the card networks themselves charge a fee to assess and route each transaction. These fees are sometimes called assessment fees and are also set by the networks. They are smaller than interchange but still contribute to the total MDR.

Acquirer or provider margin. The final component is the margin charged by your payment provider or acquirer — the company that gives you the ability to accept card payments. This covers the provider's platform costs, risk management, fraud tooling, customer support and profit margin. This is the component that varies most between providers and is the one you can influence by choosing a competitive all-in-one platform.

Payment providers quote MDR in different ways, and the pricing model affects both how easy it is to understand your costs and how predictable your fees will be month to month.

Flat-rate pricing gives you one fixed percentage (and sometimes a fixed per-transaction amount) for all card transactions, regardless of the underlying interchange. One.ooo uses this model: 2.7% plus USD 0.50 for domestic cards and 3.4% plus USD 0.50 for international cards. This is the simplest model for SMEs because you can forecast your payment costs precisely using just your sales volume and average transaction value. There are no surprises when card types change.

Blended pricing is similar to flat-rate but may vary across card categories (credit vs debit, consumer vs corporate) without full transparency into why the rates differ. Providers using blended pricing often show you a headline rate that applies to standard consumer cards but apply higher rates to premium or international cards without clearly breaking these out.

Interchange-plus pricing passes the exact interchange cost through to the merchant and adds a transparent provider margin on top. For very high-volume businesses this can be cheaper than flat-rate, but it means your effective rate fluctuates month to month as your card mix changes. It also requires more sophisticated reconciliation to understand what you actually paid. For most Singapore SMEs and growing businesses, flat-rate pricing is the easiest model to plan around and the least likely to produce unexpected invoice line items.

Singapore merchants typically see MDRs ranging from around 1.5% for domestic debit cards at large acquirers to 3.5% or more for international credit cards, depending on the provider and pricing model. The domestic vs international distinction matters in Singapore because the city-state draws a significant volume of cross-border transactions from travellers and regional e-commerce customers — and international cards usually carry a higher interchange cost that flows through to your MDR.

With one.ooo, the pricing is straightforward: domestic card transactions are charged at 2.7% plus USD 0.50, and international card transactions are charged at 3.4% plus USD 0.50. There is no setup fee and no monthly fee, so you pay only when you process a payment. That structure is easy to model against your order volume and average transaction size.

One.ooo accepts all the major card brands — Visa, Mastercard, American Express, JCB and UnionPay — as well as Apple Pay and Google Pay for contactless and mobile checkout. PayNow is also supported for customers who prefer to pay directly from their Singapore bank app, which typically carries a lower fee than card processing. If your business processes meaningful card volume and you would like to discuss volume discount pricing, contact the sales team. You can see the full rate card and get started on the one.ooo pricing page.

While you cannot change interchange rates set by card networks, there are practical steps Singapore businesses can take to lower their effective MDR — the blended cost across all transactions.

Encourage PayNow where it makes sense. For domestic B2C transactions, offering PayNow as a checkout option lets customers pay via real-time bank transfer at a lower processing cost than a card transaction. If your average order value is modest, the difference adds up over volume.

Keep your card data clean to reduce downgrades. Card transactions can be charged at a higher rate if they are processed incorrectly — for example, missing required fields or failing to capture authorisation codes. Using a platform with reliable card data handling reduces the risk of transactions being downgraded to higher-rate categories.

Consolidate payment channels onto one platform. Running separate providers for online payments, in-store terminals and FX introduces multiple fee schedules, reconciliation gaps and duplicated costs. An all-in-one platform gives you a single rate structure across channels and one view of what every transaction costs.

Ask about volume discounts as you scale. One.ooo offers volume-based discount pricing for businesses processing higher transaction volumes. As your monthly card revenue grows, it is worth opening a conversation with the sales team about a rate that reflects your volume. See the full breakdown of card and transfer costs in our guide to payment processing fees in Singapore.

Regulated payment services are provided by Airwallex (Singapore) Pte. Ltd., a MAS-licensed Major Payment Institution under the Payment Services Act 2019. ONE Payments acts as a technology provider and merchant service facilitator.

ONE Payments Pte. Ltd. (UEN 202324291R) is registered in Singapore and operates as a technology and merchant services platform. The pricing and capabilities described on this page are provided by ONE Payments; payment processing, fund holding and settlement of regulated payment activities are carried out by the licensed regulated partner named above. Information is provided for general guidance only and does not constitute financial, legal or regulatory advice. Confirm the latest pricing and available services when onboarding. Contact the ONE Payments team for details.