Every time a customer pays by card, the business accepting that payment incurs a cost. These costs are collectively known as merchant service charges — the fees that payment processors, acquirers, and card schemes levy for enabling card transactions. For UK businesses, understanding merchant service charges is essential to managing costs, choosing the right provider, and ensuring you are not paying more than you should.
This guide explains exactly what merchant service charges are, how they are calculated, what typical UK rates look like, and how you can reduce what you pay — particularly if you take payments over the telephone.
What Are Merchant Service Charges?
Merchant service charges (sometimes called merchant fees, card processing fees, or payment processing charges) are the fees a business pays to accept card payments. When a customer taps, inserts, or keys in their card details, the transaction passes through several parties — each of which takes a small fee from the total.
These charges typically include three core components:
- Interchange fee — paid to the customer's card-issuing bank. This is the largest component and is set by the card schemes (Visa, Mastercard). In the UK, interchange fees on consumer debit cards are capped at 0.2% and consumer credit cards at 0.3%, following EU-era regulations retained after Brexit.
- Scheme fee — paid to the card scheme itself (Visa or Mastercard) for using their network infrastructure. Scheme fees are typically small — often 0.02% to 0.05% — but they vary by transaction type and are increasingly complex.
- Acquirer markup — the fee your payment processor or acquiring bank charges for their service. This is where providers compete on price, and where you have the most room to negotiate.
Together, these three elements make up the total merchant service charge on every card transaction. The exact amount depends on several factors, which we will cover in detail below.
How Merchant Service Charges Are Calculated
There are two main pricing models used by UK payment processors: interchange plus plus (IC++) and blended rates. Understanding the difference is critical to evaluating whether you are getting a fair deal.
Interchange plus plus (IC++)
IC++ pricing breaks down every transaction into its three components — interchange, scheme fee, and acquirer markup — and shows you exactly what you are paying for each. The interchange and scheme fees are passed through at cost, and you pay a fixed markup on top.
For example, a £100 consumer debit card transaction might break down as:
- Interchange: £0.20 (0.2%)
- Scheme fee: £0.03 (0.03%)
- Acquirer markup: £0.10 (0.1%)
- Total: £0.33 (0.33%)
IC++ is the most transparent pricing model. You can see exactly where your money goes, verify that interchange and scheme fees match published rates, and compare acquirer markups between providers on a like-for-like basis. It is generally recommended for businesses processing higher volumes.
Blended rates
Blended pricing combines all three fee components into a single percentage (and sometimes a fixed pence-per-transaction fee). The processor quotes you one rate — say 1.4% + 20p — regardless of the card type, scheme, or transaction method.
Blended rates are simpler to understand and predict, which is why providers like Stripe, Square, and SumUp use them. However, they are almost always more expensive overall because the blended rate must cover the processor's costs on the most expensive transaction types (commercial credit cards, international cards) as well as the cheapest.
If most of your transactions are domestic consumer debit cards — where interchange is capped at 0.2% — you are effectively subsidising the higher costs of rarer card types when you pay a blended rate of 1.4% or more.
Tiered pricing
Some traditional acquirers use tiered pricing, which groups transactions into categories — qualified, mid-qualified, and non-qualified — each with a different rate. This model lacks transparency and makes it difficult to understand what you are actually paying. It is increasingly uncommon in the UK market, but if your provider uses tiered pricing, it is worth reviewing your statement carefully.
Typical UK Merchant Service Charge Rates
Rates vary significantly depending on your provider, business type, and transaction profile. However, the following ranges are typical for UK businesses in 2026:
- Domestic consumer debit cards: 0.3% to 0.6% on IC++; 1.0% to 1.5% on blended rates
- Domestic consumer credit cards: 0.5% to 0.9% on IC++; 1.4% to 2.0% on blended rates
- Commercial and corporate cards: 1.5% to 2.5% (interchange is not capped on commercial cards)
- International cards: 1.5% to 3.0% depending on region and card type
- Per-transaction fees: 1p to 20p per transaction, depending on provider and plan
Monthly fees, PCI compliance fees, gateway fees, and terminal rental charges may also apply on top of the per-transaction costs. Always ask for a full fee schedule before committing to a provider.
What Affects Your Merchant Service Charge Rate?
Several factors determine the rate you pay. Understanding these helps you negotiate better terms and structure your payment acceptance to minimise costs.
Industry and risk profile
Some industries attract higher merchant service charges because of elevated chargeback rates, fraud risk, or regulatory complexity. Travel, gambling, and subscription services typically pay more than retail, professional services, or healthcare. Your merchant category code (MCC) influences the interchange rate applied to your transactions.
Transaction volume and value
Higher-volume businesses have more negotiating leverage. If you process £50,000 or more per month, you should be on IC++ pricing and actively negotiating your acquirer markup. Even modest volume growth can justify a rate review.
Card type
Consumer debit cards are the cheapest to accept. Consumer credit cards cost more. Commercial, corporate, and purchasing cards carry the highest interchange rates because they are exempt from the consumer interchange caps. If your business serves other businesses, your average merchant service charge will be higher.
Card-present vs card-not-present
Transactions where the physical card is present (chip and PIN, contactless) carry lower interchange rates than card-not-present (CNP) transactions — such as online payments, telephone payments, and mail-order payments. CNP transactions have higher fraud rates, which is reflected in higher interchange fees.
For businesses that take payments over the telephone, this is a particularly important consideration. Phone payments are classified as CNP transactions and attract higher interchange rates than in-store payments. However, using secure payment technology can help demonstrate lower risk and potentially improve your rate profile over time.
Authentication and security
Transactions authenticated with 3D Secure (Visa Secure, Mastercard Identity Check) may attract lower interchange rates than non-authenticated CNP transactions. Using a payment gateway that supports strong customer authentication can help reduce your costs as well as your fraud exposure.
Settlement currency and region
Domestic transactions (UK card, UK acquirer) are cheaper than cross-border transactions. If you accept payments from international customers, those transactions will carry higher interchange and scheme fees. Currency conversion charges may also apply.
Phone Payment Merchant Service Charges
Businesses that take payments over the telephone face specific considerations when it comes to merchant service charges.
Why phone payments cost more
Telephone payments are card-not-present transactions. The card is not physically read by a terminal, so the transaction carries a higher fraud risk from the card scheme's perspective. This means higher interchange rates compared to in-store chip-and-PIN or contactless payments.
Additionally, phone payments historically carried significant PCI DSS compliance costs. Businesses that took card details verbally over the phone needed extensive security infrastructure — network segmentation, encrypted storage, pause-and-resume call recording, and annual compliance assessments. These compliance overheads added substantially to the true cost of accepting phone payments.
How secure technology reduces the total cost
Modern DTMF-masking technology — where customers key in card details on their telephone keypad rather than reading them aloud — transforms the cost equation for phone payments. By ensuring card data never enters your contact centre environment:
- PCI compliance costs drop dramatically. Your contact centre is descoped from PCI DSS, eliminating the need for expensive security controls, network segmentation, and annual assessments.
- Call recording costs reduce. No need for pause-and-resume technology. You can record 100% of every call.
- Fraud risk decreases. Card data cannot be overheard by agents, leaked from recordings, or stolen from your systems — reducing chargebacks and disputes.
- Staff training costs fall. Agents no longer need to be trained on handling sensitive card data securely.
When you factor in these savings, the total cost of accepting phone payments with secure technology can be significantly lower than traditional methods — even though the per-transaction interchange rate remains higher than card-present transactions.
Choosing a provider for phone payments
When comparing merchant service providers for telephone payments, look beyond the headline transaction rate. Consider the total cost of ownership: transaction fees plus PCI compliance costs plus technology costs plus staff training plus fraud losses. A provider offering 1.2% per transaction but requiring expensive PCI infrastructure may cost more overall than a provider charging 1.5% that includes PCI-descoping technology.
How to Reduce Your Merchant Service Charges
There are several practical steps UK businesses can take to lower their merchant service charges without compromising service quality or security.
1. Switch to IC++ pricing
If you are on blended rates and processing more than £10,000 per month, request a move to IC++ pricing. The transparency alone often reveals that you have been overpaying, and the cost difference can be substantial — particularly if most of your transactions are domestic consumer debit cards.
2. Negotiate your acquirer markup
Interchange and scheme fees are non-negotiable — they are set by Visa and Mastercard. But the acquirer markup is entirely negotiable. Get quotes from multiple providers, and use competing offers as leverage. Even a 0.05% reduction on the acquirer markup adds up quickly at volume.
3. Encourage debit card payments
Consumer debit card transactions cost roughly half as much as credit card transactions in interchange fees. Where appropriate, encourage customers to pay by debit card. Some businesses offer small incentives or simply make debit the default payment method in their systems.
4. Use 3D Secure authentication
Authenticating CNP transactions with 3D Secure can reduce interchange rates and shifts chargeback liability to the card issuer. Ensure your payment gateway supports the latest version of 3D Secure for both online and telephone payment flows.
5. Review your statements regularly
Merchant service charges can creep up over time as scheme fees increase and acquirers adjust rates. Review your monthly statements at least quarterly, and challenge any fees you do not recognise. Pay particular attention to PCI non-compliance fees — these are easy to eliminate by maintaining your PCI certification.
6. Reduce chargebacks and fraud
High chargeback rates can trigger penalty fees and rate increases from your acquirer. Invest in fraud prevention, clear transaction descriptors, and prompt customer service to keep disputes to a minimum.
7. Consider your payment mix
If you accept payments through multiple channels — in-store, online, and telephone — analyse the cost of each channel separately. You may find that investing in more efficient technology for your most expensive channel (often telephone) delivers disproportionate savings.
Paytia's Transparent Pricing Approach
At Paytia, we believe businesses should know exactly what they are paying and why. Our approach to merchant service charges is built on three principles.
No hidden fees
We provide a complete, itemised fee schedule before you sign anything. Transaction rates, monthly fees, PCI compliance costs (or the absence of them), and any other charges are laid out clearly. There are no surprise charges on your first statement.
PCI costs included, not added
Because Paytia's DTMF-masking technology descopes your contact centre from PCI DSS, you do not face the separate PCI compliance costs that traditional providers levy. There are no annual PCI assessment fees, no non-compliance penalties, and no expensive infrastructure requirements. The security is built into the platform.
Total cost of ownership focus
We encourage businesses to compare total cost of ownership — not just the headline transaction rate. When you factor in eliminated PCI compliance costs, removed pause-and-resume technology, reduced fraud losses, and lower training overheads, Paytia consistently delivers a lower total cost than providers who quote a lower per-transaction rate but pass on significant hidden costs elsewhere.
Take a product tour to see how Paytia's secure payment platform works in practice, or contact us for a personalised cost comparison based on your transaction volumes and payment channels.
Frequently Asked Questions
What is a typical merchant service charge in the UK?
For domestic consumer debit cards, merchant service charges typically range from 0.3% to 0.6% on transparent IC++ pricing, or 1.0% to 1.5% on blended rates. Credit card transactions cost more, and commercial cards carry the highest charges. The exact rate depends on your provider, volume, industry, and transaction type.
Why do card-not-present transactions cost more?
Card-not-present transactions — including online, telephone, and mail-order payments — carry higher fraud risk because the physical card is not verified at the point of sale. Card schemes set higher interchange rates for CNP transactions to reflect this increased risk. Using secure authentication methods can help mitigate the cost difference.
Can I negotiate my merchant service charges?
Yes. While interchange and scheme fees are set by Visa and Mastercard and cannot be negotiated, the acquirer markup — the fee your payment processor charges — is fully negotiable. Businesses processing higher volumes have more leverage, but even smaller businesses should request quotes from multiple providers and compare like for like.
What is the difference between IC++ and blended pricing?
IC++ (interchange plus plus) separates every transaction into its three components — interchange, scheme fee, and acquirer markup — giving you full transparency. Blended pricing combines everything into a single rate. IC++ is almost always cheaper for established businesses because blended rates must cover the processor's costs on the most expensive card types, meaning you overpay on cheaper transactions.
Are merchant service charges tax-deductible?
Yes. Merchant service charges are a legitimate business expense and are fully deductible against your taxable profits. They should be recorded as a cost of sale or payment processing expense in your accounts. VAT is not charged on interchange fees, but some acquirer and gateway fees may include VAT — check your statements.
How do phone payment merchant charges compare to in-store charges?
Phone payments typically attract higher per-transaction interchange rates because they are classified as card-not-present. However, the total cost comparison must include PCI compliance overheads, technology costs, and fraud losses. Businesses using secure DTMF-masking technology for phone payments can achieve a lower total cost of acceptance than those relying on traditional verbal card capture methods.
What are PCI non-compliance fees?
Many acquirers charge a monthly PCI non-compliance fee (typically £20 to £50 per month) to merchants who have not completed their annual PCI DSS Self-Assessment Questionnaire. This fee is easily avoided by maintaining your PCI certification. Using a PCI-descoping solution like Paytia can simplify the assessment process significantly.
Understanding your merchant service charges is the first step to controlling them. Whether you accept payments in-store, online, or over the telephone, knowing what you pay, why you pay it, and how to reduce it directly improves your bottom line. Explore Paytia's merchant services or get in touch for a free cost analysis.