Payments4 min readUpdated October 15, 2026

What Is a Payment System?

Payment system definition (BIS, EU law), the 5 main types with examples like Visa, Fedwire, ACH and FedNow, and what an authorized payment means.

Nick Bonnassies, CMO at Tagada · checked against 9 sources

Article summary

TL;DR

A payment system is a set of instruments, procedures and rules for transferring funds between participants, together with those participants and the entity that runs it. That is the definition used by central banks. Card networks like Visa, bank wire systems like Fedwire, ACH, and instant schemes like FedNow are all payment systems.

Central banks define a payment system as instruments, procedures and rules for moving funds between participants, plus the participants and the operator.
The main types are card networks, large-value systems (RTGS), retail batch systems like ACH, instant payment systems and closed-loop networks.
In a card payment, an authorized payment is one the issuer approved. In EU law, it is one the payer consented to.
Online stores reach card payment systems through a payment processor and an acquirer, not directly.

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People use "payment system" for anything from a checkout page to a national bank network. Central banks and regulators use it in a narrower sense, and that sense is the one that explains how your money actually moves.

What is a payment system?

The Committee on Payments and Market Infrastructures, the body of central banks hosted by the BIS, defines a payment system as "a set of instruments, procedures, and rules for the transfer of funds between or among participants; the system includes the participants and the entity operating the arrangement."1

EU law adds two versions. PSD2 calls it "a funds transfer system with formal and standardised arrangements and common rules for the processing, clearing and/or settlement of payment transactions," where a payment transaction is any act of "placing, transferring or withdrawing funds."2 The Settlement Finality Directive is stricter: a "system" has three or more participants, common rules, and is formally designated by a Member State.3

So a payment app is not a payment system by itself. It is an entry point into one.

Types of payment systems, with examples

Central banks split systems by size: retail systems handle "a large volume of relatively low-value payments," while large-value systems handle "large-value and high-priority payments."1

Type	How it works	Example
Card network	The acquirer sends the transaction through the network to the card issuer for approval	Visa: the acquirer sends it "through VisaNet" to Visa, which sends it to the issuer. Visa does "not issue cards, extend credit or set rates" for cardholders.4
Large-value (RTGS)	Each payment settles on its own, in real time	Fedwire Funds: "immediate, final, and irrevocable once processed."5 T2, the Eurosystem's RTGS, replaced TARGET2 in March 2023.6 See also CHIPS.
Retail batch (ACH)	Banks send files of credits and debits under shared rules	ACH Network: Nacha writes the rules; the Federal Reserve and The Clearing House operate it.7 In Europe, SEPA.
Instant	Account-to-account transfers in seconds, all day, every day	FedNow, live since July 20, 2023, built for 24x7x365 processing.8 SEPA Instant in euros.
Closed loop	One company runs both ends: issuer and acquirer	American Express. See closed loop.

India's UPI, piloted by NPCI with 21 banks in April 2016, puts several bank accounts into one mobile app.9 For speed and limits across instant rails, see real-time payments.

Payment system and authorized payment

"Authorized" means two different things, and both apply to the same payment.

Network authorization. In a card system, the issuer checks the balance or credit line and approves or declines. See authorization.
Legal authorization. Under PSD2, a payment is "authorised only if the payer has given consent." Without consent it is unauthorized, and consent can be withdrawn until the payment order becomes irrevocable.2
Clearing. Participants transmit and reconcile the payment details, sometimes netting them.1 See clearing.
Settlement. Funds actually move between the participants' accounts. See settlement.

What a payment system means for an online store

You never connect to Visa or Fedwire yourself. A payment processor and an acquirer connect you to card systems; see acquirer processing. The networks charge for that access through scheme fees. Bank systems like ACH and SEPA reach you through your bank or your processor. For the difference between the gateway and the processor in that chain, read payment gateway vs payment processor.

How Tagada helps

One checkout, several processors

Tagada routes payments across TagadaPay and processors such as Stripe, NMI and Airwallex with one logic, and cascades to the next one when the first is down or times out. Tagada follows Visa and Mastercard rules and the laws that apply to payments.

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Seeing TagadaPay on your card statement?

TagadaPay is a payment processor used by online merchants. The merchant's name usually follows TagadaPay on the statement line. If you have a question about the charge, contact that merchant first. If you don't recognize the purchase, contact the bank that issued your card.

Updated on October 15, 2026

Nick Bonnassies

CMO at Tagada

CMO at Tagada. Before Tagada, Nick built direct-to-consumer brands that generated over $115M in sales, raised over $25M in crowdfunding and sold two of them. He also works as a fractional CMO on marketing operations and AI systems.

Frequently asked questions

What are the main components of a payment system?

Three things, in the central bank definition: the instruments used to pay (cards, transfers, direct debits), the procedures and rules for moving funds, and the participants, including the entity that operates the system. In practice, every system also needs clearing (exchanging and reconciling payment details) and settlement (the final transfer of funds).

What is a bank payment system?

A system banks use to move money between their accounts. Large-value systems like Fedwire in the US and T2 in the euro area settle each payment one by one in central bank money. Retail systems like the ACH Network and SEPA handle large volumes of smaller payments such as payroll and bill payments.

Is a payment processor a payment system?

No. A payment system is the network and its rules, such as Visa or the ACH Network. A payment processor is a company that connects merchants to those systems: it sends authorization requests, then submits payments for clearing and settlement.

What makes a payment authorized?

In a card payment, the card issuer approving the request. In EU law, the payer's consent: PSD2 says a payment transaction is authorized only if the payer has given consent, and is unauthorized without it. Consent can be withdrawn until the payment order becomes irrevocable.

Sources

Checked October 15, 2026

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