What is remittance advice in accounts receivable?

Remittance advice is the note a customer sends with a payment to explain which invoices that payment covers. It tells the supplier how to split a single deposit across the right open invoices, so the cash lands where it belongs instead of sitting unapplied.

In B2B, customers rarely pay one invoice at a time. A buyer might send one wire that settles eight invoices, minus a credit and a short-paid disputed line. Remittance advice is the key that unlocks that payment. Without it, the receivables team is left guessing which invoices to close.

What is remittance advice?

It is a record that accompanies or references a payment and lists the invoices being paid. The payer creates it; the supplier uses it to apply the cash. The detail can be rich (invoice numbers, amounts, deductions, reasons) or as thin as a payment reference typed into a bank transfer.

Think of it as the payer answering the question every AR team asks when money arrives: "What is this for?"

Types of remittance advice

Remittance advice shows up in several formats, and most AR teams handle all of them at once:

• Email or PDF remittance. The most common in mid-market B2B. An AP clerk emails a remittance file or attaches a PDF listing invoice numbers and amounts.
• EDI 820. A structured electronic remittance used by larger trading partners. It carries invoice-level detail in a machine-readable format.
• Portal remittance. Some buyers post remittance detail in a supplier or AP portal that the supplier has to log into and pull.
• Bank or lockbox data. Payment details captured in the bank file or by a lockbox provider, often with limited reference information.
• Check stub. For paper checks, the detail printed on the stub attached to the check.

The variety is the problem. The same customer base will send remittance five different ways, which is why parsing it consistently is hard.

What remittance advice includes

A complete remittance gives the AR team everything needed to apply cash without a single email back to the customer:

• Payer name and the payment date
• Total payment amount and the method (wire, ACH, check)
• A line for each invoice being paid, with invoice number and amount
• Any deductions, credits, or short payments, ideally with a reason code
• A reference or payment ID to tie it to the bank deposit

When all of that is present and accurate, applying the payment is mechanical. When a reason code is missing or an amount does not tie out, the payment becomes an exception that a person has to chase.

Why remittance advice matters for cash application

Cash application is the process of matching incoming payments to open invoices. Remittance advice is its raw material. Strong remittance data means high straight-through matching: the payment posts, the invoices close, and DSO reflects reality. Weak or missing remittance data means cash sits in a suspense account while someone reverse-engineers what it was for.

It also surfaces short payments and deductions early. A line that pays 9,200 against a 10,000 invoice, flagged as a freight dispute, tells you exactly what to investigate. Read more in our guide to cash application, where remittance matching is the first step.

Automating remittance processing

The manual version of this work is slow and error-prone. Someone opens each email, reads the PDF, types invoice numbers into the ERP, and resolves the lines that do not match. Across hundreds of payments a week, that is a full-time job that still leaves cash unapplied at month end.

Rex reads remittance advice wherever it arrives, email, PDF, EDI, or portal, and parses the invoice-level detail automatically. It matches each line to the right open invoice, posts the cash, and codes short pays and deductions to the correct reason so they route for resolution. The payments that tie out clean are applied without anyone touching them. Only the genuine exceptions, a mismatch or an unexplained deduction, surface for a person to decide.

See how Rex turns messy remittance into applied cash, end to end.