What Is an ARN (Acquirer Reference Number)? How to Find and Track One

An ARN, short for acquirer reference number, is a code that uniquely identifies one card payment as it moves between banks — typically 23 characters on the major card schemes.

The classic reason to need one is a refund that hasn't arrived.The merchant says the money left. The bank says nothing came in. The ARN is the tracking reference both sides can use to trace what actually happened. Checkout.com, Chargebacks911, and Rapyd all describe the Visa and Mastercard version the same way: 23 digits, created on the acquiring side, used to trace a specific transaction between banks. Don't treat 23 as universal, though: Solidgate's glossary notes ARN length can range from 8 to 30 characters depending on the card network.

What an ARN does — and when it exists

Think of the ARN as the payment's tracking number. Money moving between banks doesn't carry a parcel label — the ARN is that label.

Three details worth knowing:

• It doesn't exist immediately. The ARN is assigned during clearing — when the acquirer (the institution accepting card payments on the merchant's behalf) submits the transaction to the card network for settlement. Solidgate's glossary states this directly. An authorized-but-not-captured payment has no ARN yet.
• It follows refunds too. Adyen's documentation notes the ARN can be used to track status changes like capture, refund, and chargeback (a bank-forced payment reversal). It is a tracking reference for the refund's journey — useful for confirming processing status, not proof the money has landed in the customer's account.
• Which networks use ARNs. Checkout.com describes ARNs on Visa and Mastercard. Adyen's documentation also lists JCB and Diners. And American Express's own network specifications define a 23-character Acquirer Reference Number field in clearing messages, so Amex transactions carry one as well. What differs in practice is whether your provider exposes it — the provider docs above cover Visa and Mastercard (Adyen's also JCB and Diners); ask your PSP what it can share for other schemes.

Sources: Checkout.com, "What is an ARN?" (published 27 September 2023); Adyen Help, "Where can I find the ARN?"; Solidgate glossary (assignment during clearing); American Express Global Network Specifications — Financial/Non-Financial, October 2022 (Acquirer Reference Number, format X(23), positions 223–245 in the 1240 presentment layout). All accessed 9–12 July 2026.

Which "ARN" do you actually mean?

Three unrelated things share this acronym. If you searched "ARN number," check you're in the right row:

Sources: Bajaj Finserv, "How to Get an ARN (AMFI Registration Number)"; USCIS Glossary, "A-Number / Alien Registration Number" (unique 7-, 8- or 9-digit DHS identifier)Accessed 9–22 July 2026.

How to track a refund with an ARN

The classic case, in one forum user's words: "Sender claims that the refund has been successful and gave me a long number called ARN number" (MoneySavingExpert thread).

You cannot generate an ARN yourself. Who does what:

If you are the customer:

1. Ask the merchant's support for the ARN of your refund.
2. Give the ARN to your card issuer — the bank behind your card.
3. Add the date, amount, and merchant name so the agent can match it.
4. Ask them to trace the credit. Persistence helps — as the forum thread below shows, front-line staff don't always know the process.
5. If the agent can't proceed, ask for the disputes or back-office team.

If you are the merchant:

1. Confirm the refund was actually submitted for clearing, not just created.
2. Get the ARN from your acquirer or payment service provider (PSP) — the company that processes your payments. Adyen, for example, exposes it in its Customer Area under the payment's events.
3. Send the customer the ARN with the refund date and amount.
4. Tell them to quote it to their bank, not to the card network.
5. If the trace stalls, escalate through your PSP with the ARN attached.

When the trace gets ugly

That same forum thread shows the realistic failure mode. The refund went to a closed account. The bank first said it "cannot do anything and it has been bounced back." Only after the customer supplied the ARN did the bank reply: "now they said they are investigating it!" Another user's verdict on why this happens: "Banks... don't train their call-centre staff adequately."

Practical reading of that story: an ARN doesn't guarantee the money reached a usable account. It gives the banks a concrete reference they can use to trace the payment, instead of a shrug. And what happens to a credit sent to a closed account varies by institution and country. The US consumer regulator's guidance describes institutions that unilaterally reopen closed accounts to accept incoming credits — a practice it calls unfair — and notes that institutions can instead decline such transactions, which sends the payment back and alerts the sender. So don't assume one outcome. Customers should push the issuing bank to trace the credit; merchants should watch for a returned refund before re-issuing.

Sources: MoneySavingExpert forum, "ARN and Refund" — consumer reports quoted verbatim; CFPB Consumer Financial Protection Circular 2023-02 (institutions sometimes unilaterally reopen closed accounts to accept credits — deemed unfair; the circular notes they can instead decline such transactions). Accessed 9–12 July 2026.

Sources

1. Checkout.com — "What is an ARN (Acquirer Reference Number)?" — 23-digit (Visa/Mastercard) definition, refund and dispute uses. Published 27 September 2023; accessed 9 July 2026.
2. Adyen Help — "Where can I find the Acquirer Reference Number (ARN)?" — scheme list (Visa, Mastercard, JCB, Diners), capture/refund/chargeback status tracking, Customer Area path. Accessed 9 July 2026.
3. American Express — Global Network Specifications: Financial/Non-Financial (October 2022) — Acquirer Reference Number (ARN) field, format X(23), positions 223–245, 1240 presentment message layout. Accessed 12 July 2026.
4. Solidgate — "Acquirer reference number (ARN)" (glossary) — assignment during clearing. Accessed 9 July 2026.
5. Chargebacks911 — "What Is an Acquirer Reference Number?" — 23-digit (Visa/Mastercard) corroboration, dispute context. Published 27 November 2024; accessed 9 July 2026.
6. Rapyd — "What Is an ARN (Acquirer Reference Number)" — 23-digit (Visa/Mastercard) corroboration. Accessed 9 July 2026.
7. CFPB — Consumer Financial Protection Circular 2023-02 — how institutions handle credits to previously closed accounts. Accessed 12 July 2026.
8. MoneySavingExpert Forum — "ARN and Refund" — the consumer refund-tracing experiences quoted verbatim in this guide. Accessed 9 July 2026.
9. Bajaj Finserv — "How to Get an ARN (AMFI Registration Number)" — the AMFI Registration Number (India) in the disambiguation table. Accessed 9–22 July 2026.
10. USCIS — Glossary: "A-Number / Alien Registration Number" — the 7–9 digit DHS identifier in the disambiguation table. Accessed 9 July 2026.

Wondering how approvals and declines work before a refund ever happens? Start with our payment acceptance guide.