A payment gateway captures your customer's card details and passes them on securely. A processor sends the payment through the card networks and returns the answer. An acquirer is the bank that settles the money to a business, and a payment facilitator bundles all of this into one product you can sign up to. For most small businesses, the facilitator is the only one you contract with, so the questions that matter are who settles your money, who can hold it back, who sets your rate and who you call.
In this article
The short version
- A gateway captures card details; a processor routes the payment.
- Most small businesses contract with a payment facilitator, not an acquirer.
- Whoever settles your money can usually hold some of it back.
- Only your provider's margin is really negotiable.
- Card customers won't notice a switch; direct debit mandates can move by bulk change.
The parties in a card payment
Five roles sit behind a card payment, and one company often plays several of them.
| Role | What it does | Do you contract with it? |
|---|---|---|
| Gateway | Captures card details at checkout and passes them on securely | Only if you buy it separately |
| Processor | Routes the payment through the card networks and returns approved or declined | Rarely, and usually through someone else |
| Acquirer | The bank licensed by the card schemes to settle money to businesses | Yes, if you hold a merchant account in your own name |
| Payment facilitator | Sells the whole chain as one product and signs you up underneath its own acquiring arrangement | Yes, with almost every self-serve provider |
| Card scheme | Visa or Mastercard, which set the network rules and fees | Never directly |
Gateway and processor used to be two separate purchases: a gateway for your website and a merchant account from a bank to receive the money. Today most providers include both, so the difference mostly describes what happens in the seconds after your customer taps Pay. It still helps when a payment fails. A declined card is the card issuer's decision, while a payment that never reaches the bank for approval usually points to a set-up problem on your side.
If you're asking a provider what it does, asking which of these roles it performs itself, and who performs the rest, tends to tell you more than the product name.
Who your contract is with
With a payment facilitator, you're a sub-merchant. The facilitator has the relationship with the acquirer, and you sign the facilitator's terms. That's why you can usually be live within a day or two. It also means your terms are the facilitator's and can change with notice, your ability to take cards depends on its acquiring arrangement, and underwriting decisions about your business are made under its rules. A sector one facilitator turns down may be accepted by another.
With a merchant account in your own name, the acquirer underwrites you directly, and your terms are in a contract you negotiated. It takes longer to set up and gives you more control, which tends to matter once card payments are a large share of your income.
Regulation adds another layer. Some providers are authorised by the FCA in their own right, and others provide payment services as an agent or partner of a firm that is. An agent can only provide its principal's payment services, so it's worth checking the Financial Services Register for the provider and any firm it names as its partner. Adfin, for example, delivers payment services through FCA-regulated partners Adyen N.V., Stripe Payments Europe Ltd and Tink Financial Services Ltd.
Who can hold your money and who sets your rate
Whoever settles money to you can usually hold some of it back. Most providers' terms let them keep a reserve against refunds and chargebacks, delay payouts while they review unusual activity, or suspend the service in certain circumstances. Terms like these are normal across the industry. Ask what would trigger a hold, how long one would last and how you'd be told.
Payout timing and how fees are taken matter as well. Some providers pay out daily, others weekly, and many deduct their fees before paying you, so a payout never adds up to the invoices it covers. Adfin pays out every weekday without taking anything off and invoices its fee separately, so each payout adds up to the invoices it covers.
No single party sets your whole card rate. The fee has three parts: interchange, which goes to your customer's card issuer and is capped by law at 0.2% on UK personal debit cards and 0.3% on personal credit cards; scheme and processing fees charged by Visa and Mastercard, which aren't capped; and your provider's margin. Only the margin is really open to negotiation. Business and commercial cards fall outside the interchange caps, which is why most providers charge more for them.
What your customers notice if you switch
Changing card provider is usually invisible to your customers. A new payment link on your next invoice simply works, because no standing permission is held on your behalf. The exception is saved cards: card details stored by your old provider may not move across, so a customer who pays on file might need to enter their card once more.
Direct debit is different, because your customers have signed mandates with your current provider. There are two ways to move them. The Bacs bulk change process transfers existing mandates to the new provider, and your customers don't need to sign anything, though they're told about the change. Or your customers sign a new mandate with the new provider.
If you move to Adfin with 10 or more mandates, they move through the Bacs bulk change process and your clients don't re-sign. Below 10, each client signs a new mandate. Either way, you then run card, pay by bank and direct debit from the same invoice, and Adfin's collection agents can chase unpaid invoices and retry failed collections within rules you set.
Common questions
What's the difference between a payment gateway and a payment processor? The gateway captures the card details and passes them on securely. The processor sends the payment through the card networks and returns approved or declined. Most providers include both in one product.
Do I contract with the acquirer or with the provider I signed up to? With the provider, in almost every self-serve product. It acts as a payment facilitator, signing you up under its own relationship with an acquirer.
Who can hold or freeze my funds? Whoever settles money to you. Most providers' terms allow them to keep a reserve or delay payouts in certain circumstances, so read that part of the agreement before you sign.
Who decides the card rate I pay? Three parties between them: the card issuer's interchange, the card schemes' fees and your provider's margin. Only the margin is usually negotiable.
Will my customers notice if I change payment provider? Card payers usually won't, except where they've saved a card with your old provider. Direct debit customers can be moved through a Bacs bulk change without signing anything, or asked to sign a new mandate.
How do I check a payment provider is regulated? Search the FCA's Financial Services Register for the provider and for any firm it names as its regulated partner.
Sources
- FCA Handbook - PERG 15.4, agents of payment institutions (accurate as of October 2026) https://handbook.fca.org.uk/handbook/PERG/15/4.html
- FCA - Financial Services Register (accurate as of October 2026) https://register.fca.org.uk/
- Payment Systems Regulator - Market review into the supply of card-acquiring services: final report (accurate as of October 2026) https://www.psr.org.uk/media/p1tlg0iw/psr-card-acquiring-market-review-final-report-november-2021.pdf
- legislation.gov.uk - Regulation (EU) 2015/751 on interchange fees (accurate as of October 2026) https://www.legislation.gov.uk/eur/2015/751
- Adfin - FAQ (accurate as of October 2026) https://www.adfin.com/faq
- Adfin - Next-generation direct debit (accurate as of October 2026) https://www.adfin.com/direct-debit-payments
