Blended Rate vs Interchange-Plus: Which Model Fits Your Business?

Blended rate and interchange-plus are the two main ways payment processors price card transactions in Singapore. A blended rate charges one fixed percentage on every card, no matter which network or card type is used. Interchange-plus splits the cost into the actual network fee plus a separate markup, so the rate changes with every transaction. This article explains both models, shows how the numbers play out in practice, and covers what actually determines which one costs less for your business.

What is a blended rate?

The Merchant Discount Rate, or MDR, is the percentage a business pays on every card transaction it processes into its merchant account, the account an acquirer uses to settle card funds into your business bank account. A blended rate folds the interchange fee, the scheme fee, and the processor’s markup into one flat MDR percentage.

Under a blended rate, a Visa debit card, a Mastercard credit card, and an American Express card are all charged the same percentage. The payment processor absorbs the difference between what it actually pays the card networks and what it charges you, and evens it out into a single rate.

This is why blended pricing shows up so often for small and medium businesses in Singapore. One rate is easy to check against a receipt, easy to forecast, and easy to explain to whoever does your books.

What is interchange-plus pricing?

Every card transaction has three underlying cost layers: an interchange fee paid to the customer’s card-issuing bank, a scheme fee paid to the network such as Visa or Mastercard, and the processor’s own markup. Interchange-plus keeps these three cost layers visible on the statement, instead of folding them into one blended MDR.

Under this model, your statement shows the real interchange fee for each transaction, plus a fixed markup on top, usually expressed as interchange plus a set number of basis points. A local debit card and an international corporate card will show different final rates, because the underlying interchange fee is different for each.

Interchange-plus is more transparent in principle. It is also harder to read, because the rate you pay depends on exactly which cards your customers use that month.

How the numbers actually compare

Take a retail business in Singapore processing $50,000 a month in card payments. At a blended rate of 2.8%, the monthly processing cost is a flat $1,400, regardless of what mix of cards customers used.

Under interchange-plus, that same $50,000 might carry an effective rate of 2.3% in a month heavy with local debit cards, or 3.1% in a month with more international or premium cards. The dollar cost moves with the card mix, even though the markup on top of interchange stays fixed.

Neither number is universally better. A business with a stable, mostly local card mix can often do better on interchange-plus. A business with unpredictable or higher-risk transaction volume usually pays less, on average, with a blended rate, because the processor is pricing in that variability up front.

Why the model you choose affects your margin

The card mix is the deciding factor, not the label on the pricing model. A cafe that takes mostly local debit and PayNow-linked cards has a cheap card mix, and interchange-plus would likely show real savings over a blended rate. A retailer with a large share of tourist spending, corporate cards, or Amex transactions has an expensive card mix, and a blended rate protects against that volatility.

Ticket size matters too. Businesses with small, frequent transactions feel fixed per-transaction fees more than businesses with larger average tickets, so the flat-fee component of either model deserves as much attention as the percentage.

Common misunderstandings about the two models

The most common assumption is that interchange-plus is always cheaper because it looks more transparent. That is only true if your card mix is genuinely cheap to process. A business with a lot of premium or international cards can end up paying more under interchange-plus than it would under a well-priced blended rate.

The second common mistake is comparing a headline rate without checking for minimum monthly fees, statement fees, or PCI compliance charges added on top. A processor advertising a lower interchange-plus markup can still end up more expensive once these are included.

The third is assuming a blended rate charges differently depending on the card. It does not. That is the entire point of the model, and it is also the tradeoff: you give up some potential savings on cheap cards in exchange for one predictable number every month.

How to choose the right model for your business in Singapore

Start with your card mix. If you can pull a few months of statements and see mostly local debit and standard credit cards, interchange-plus is worth a proper comparison. If tourists, corporate accounts, or premium cards make up a meaningful share of your sales, a blended rate is usually the safer default.

Consider who is going to read the statement. Interchange-plus requires someone to check line items regularly to catch creeping markups or reclassified transactions. If nobody on your team has the time or the background for that, the simplicity of a blended rate has real value beyond the raw percentage.

Finally, ask for actual numbers based on your own transaction history, not a generic quoted rate. Any processor should be able to model both pricing structures against a few months of your real statements before you commit to either one.

FAQ

Is a blended rate always more expensive than interchange-plus?

No. It depends entirely on your card mix. A business with a lot of premium or international cards can pay less overall on a blended rate than on interchange-plus.

What is MDR?

MDR stands for Merchant Discount Rate. It is the percentage fee a business pays on each card transaction, covering the interchange fee, the scheme fee, and the processor’s markup.

Can I negotiate my MDR in Singapore?

Yes. MDR is set commercially between the merchant and the processor, not fixed by regulation. Volume, business type, and processing history all affect what a provider will offer.

Does GST apply to card processing fees?

GST treatment depends on the terms of your specific processing agreement. Check this directly with your provider before comparing quotes, since it affects the real cost of each rate.

How do I know which model my current provider uses?

Check your monthly statement. If every transaction shows the same percentage regardless of card type, you are on a blended rate. If the rate changes transaction to transaction, you are on interchange-plus.

Where Sambapay fits in

Sambapay is a Singapore-based Independent Sales Organization (ISO). Merchants on Sambapay get a blended card processing rate under 3%, modern terminals including the PAX A920 or A930 Pro from $20 a month, settlement in two business days, and acceptance across the major card networks and digital wallets.

If you want to see how your own card mix and volume would play out under a blended rate, the free Payment Cost Review breaks down your current statements and shows the real numbers side by side.