Acquirer Reference Number & How to Track Transactions

An Acquirer Reference Number (often shortened to ARN) is a unique 23-digit reference code assigned to a card payment as it moves through the banking system. This code helps merchants, banks, and customers trace transactions, confirm the path a payment took, and understand where it sits in the refund process.

In simple terms, it’s the digital “tracking ID” used by Visa and Mastercard networks to identify a specific card payment. Whenever a payment or refund moves between a merchant’s bank (the acquiring bank) and the customer’s bank (the issuing bank), a transaction reference number like an ARN helps everyone involved track the status.

Whether you’re trying to trace the refund, investigate a delay, or verify payments processed for bookkeeping, understanding the meaning of an acquirer reference number can help you resolve payment issues much faster.

In this guide, you’ll learn:

• What an acquirer reference number is
• How this transaction reference moves through banking networks
• Where to locate the reference code
• How businesses and customers can track transactions
• Common issues and how to fix them

What Is an Acquirer Reference Number (ARN)?

An Acquirer Reference Number is a unique code created for a card payment (Visa or Mastercard). It identifies the payment as it travels from merchant → acquiring bank → card network → issuing bank → customer account.

You might also hear it called:

• a tracking ID,
• a processor reference number,
• a card network trace code, or
• a payment identifier.

Each term refers to the same thing: a way to follow the transaction as it moves through multiple institutions.

When processed correctly, the ARN helps both the merchant and customer identify the exact point a payment reached in the banking system. This is essential for checking refunds, investigating delays, or resolving fraudulent transactions.

Why ARNs Matter

• They help banks locate a specific payment in seconds.
• They prevent duplicate refunds and chargebacks.
• They reduce customer support back-and-forth.
• They provide transparency in payment flows.
• They help merchants and customers track payments properly.

Because each identifier is unique, it avoids confusion for businesses handling dozens (or even thousands) of transactions.

Acquirer Reference Number Example

A standard 23 digit acquirer reference number may look like this:

74947627382104928371542

The acquirer reference number format follows a predictable structure used by Visa and Mastercard. While not publicly decoded, it usually includes information such as:

• the processor or acquiring bank,
• routing information inside the card network, and
• details that identify the issuing bank.

Understanding this number helps support teams trace transactions and follow a payment through each stage of its journey.

How Does an ARN Work?

To understand the acquirer reference number meaning, it helps to look at the complete payment flow.

The path looks like this:

1. Customer initiates a card payment with Visa or Mastercard
   
2. The transaction is sent to the acquiring bank
   
3. The acquirer submits it into the card network
   
4. Visa or Mastercard passes it to the issuing bank
   
5. The issuing bank posts the payment to the customer’s account

During this multi-step journey, a digital log is created. 

One part of that log is the ARN tracking number, which makes it possible to locate where the payment is at any moment.

Why this matters

Because banks and processors sometimes face delays, the ARN helps:

• merchants track transactions for reconciliation
  
• customers confirm whether their refund has reached the bank
  
• banks review routing pathways for issues
  
• both sides verify whether a transaction stalled

This helps reduce miscommunication and long support delays.

Where to Find Your Acquirer Reference Number

Finding the card network trace number depends on whether you’re the merchant or the cardholder.

If You’re a Customer

Customers can locate the ARN in:

• refund confirmation emails
• transaction details inside a banking app
• digital receipts
• support messages from the merchant
• by requesting it from the bank directly

Pro Tip: If you contact your issuing bank, simply say: “I need help tracing a card refund using a transaction reference number.”

If You’re a Merchant

Businesses can typically find the ARN reference number in:

• their payment processor dashboard
• Worldpay or merchant account reports
• refund confirmation notifications
• customer support transcripts
• internal reconciliation spreadsheets

Merchants may also see:

• merchant ID,
• merchant reference,
• merchant account identifiers,

alongside the ARN depending on the provider.

Why the ARN Is Important for Refunds

Most customers search for the ARN when a refund seems delayed. This number helps everyone involved trace the refund across multiple systems.

A refund has its own lifecycle. It needs to pass through:

• the merchant’s acquirer,
• the card network,
• and the customer’s issuing bank.

With so many steps, delays are common. The ARN helps:

• track the status of the refund,
• confirm whether it reached the issuing bank,
• resolve customer concerns quickly,
• prevent unnecessary disputes or chargebacks,
• improve overall customer experience.

Additional reading: Visa’s dispute process documentation confirms that these tracking identifiers help both sides resolve concerns efficiently.

How to Track Your ARN Number for Refunds

Here is the simple process for using the ARN number tracking to follow a refund:

Step 1 — Get the payment reference from the merchant

This may appear as:

• ARN tracking number
• card network reference
• processor tracking ID
• refund trace number

Step 2 — Contact the issuing bank

Provide:

• transaction amount
• date of refund
• last four digits of the card
• the 23-digit code

The bank can search their internal system and track payments instantly.

Step 3 — Ask the bank to confirm where the refund is

Banks can determine whether the refund:

• is in-flight
• arrived but not posted
• failed due to account mismatch
• is paused for verification

Step 4 — Allow banks time to post the refund

Posting delays (3–7 business days) are common, especially during holidays.

Step 5 — If needed, request the merchant to resend the ARN

This often solves refund disputes in minutes.

Pro Tip: Make refund tracking easier with Invoice Fly’s secure online payments system.

Common ARN Issues and Misunderstandings

Even though the acquirer reference number format is consistent, several misunderstandings occur:

1. Belief that the refund wasn’t issued

When the ARN shows it reached the issuing bank, it’s usually a posting delay—not a missing refund.

2. Confusion between ARNs and local bank references

Issuing banks sometimes use different internal IDs, which don’t replace the ARN.

3. Wrong length

Anything other than a 23 digit acquirer reference number is not valid.

4. Delay between refund initiation and code generation

It may take hours for the number to appear.

5. Acquirer Reference Numbers do NOT apply to all card types

American Express uses different tracking identifiers.

6. Time zone mismatches

Refund timestamps vary depending on the bank’s location and settlement cut-offs.

What ARN Means for Merchants

Businesses benefit from ARN visibility because it helps:

• troubleshoot refunds faster
• reduce chargebacks
• provide accurate support responses
• track transactions for reconciliation
• verify whether a customer was truly charged
• identify fraudulent transactions sooner

Merchants using digital receipts, payment portals, and transaction logs have a much easier time matching Acquirer Reference Number data.

For more helpful resources check out our guides on:

• Accepting credit card payments
• Professional invoice elements
• Payment portal glossary
  

Pro Tip: For more document retention rules, the U.S. Chamber explains how long to keep financial documents.