n8n AR Invoice Chasing: Gmail Overdue Statements & Payment Matching

Automatically chase overdue AR invoices with Gmail—using smart payment matching and consolidated statements

This n8n workflow matches your bank Payments to open Invoices in Google Sheets every weekday morning, then emails consolidated overdue statements via Gmail—including an escalation path for exceptions and a chase-log that records every collection decision.

What this workflow does

1) Weekday 7am: Payment matching & AR ledger updates

• Reads Payments and open Invoices from Google Sheets on a weekday schedule at 7am.
• Allocates each bank line to invoices by parsing references, matching exact amounts, or performing invoice-combination matching.
• Updates the Invoices tab with new balances.
• Marks each Payments line as allocated, part-allocated, or unallocated in the Payments tab.

2) Exception reporting to the AR clerk

• Collects payment-matching exceptions such as ambiguous combinations, unknown payers, short payments, or overpayments.
• Sends one consolidated report to the AR clerk via Gmail.

3) Weekday 9am: Overdue statement emails & escalation

• Runs again at 9am, loads Customers, Invoices, Payments, and the Chase log from Google Sheets.
• Chooses one collection action per customer based on grace periods, promises, disputes, unmatched cash, and minimum-balance thresholds.
• Sends a single consolidated overdue statement email per customer via Gmail.
• Escalates accounts in dispute, over credit limit, or missing an email to the account manager—or requests finance lead approval before handing off to collections.
• Appends the outcome (action, level, reason, amounts, and invoices) to the Chase log.

Use cases

• Reduce manual AR work by automating payment-to-invoice allocation in Google Sheets.
• Send timely overdue statements without sending multiple fragmented emails.
• Handle edge cases (short/overpayments, unknown payers) with a single clerk-ready exception report.

Technical details

• Scheduler: weekday runs at 7am and 9am.
• Logic/flow control: if, set, code, no op, switch.
• Messaging: Gmail for exception reporting and customer overdue statements.