Odoo Overdue Invoice Reminder Workflow: Gmail + Slack (n8n)

Odoo overdue invoices, automatically chased—every Monday

This n8n workflow pulls overdue invoices from Odoo and sends a weekly overdue digest via Gmail plus a Slack update, then escalates payment follow-ups by days overdue with tiered reminders and a 30+ day account-manager alert.

What this workflow does

• Runs on schedule: executes every Monday at 9am.
• Pulls overdue invoices from Odoo: searches account.move records for posted, unpaid invoices with due dates in the past (using data like partner_id, due date, and payment state).
• Fallback email when Odoo fetch fails: if the Odoo fetch fails, it sends the overdue ops email using Gmail.
• Normalizes and calculates overdue days: prepares invoice fields and computes how many days each invoice is overdue.
• Sends a weekly digest: aggregates all overdue invoices into an HTML digest sent by Gmail to finance, and posts a text summary to a Slack finance channel.
• Escalates by tier: routes invoices into escalation tiers based on days overdue:
  • 7–13 days
  • 14–29 days
  • 30+ days
  • Under 7 days (included in routing logic)
• Reminds customers via Gmail: for 7–13 and 14–29, looks up the customer contact in Odoo and sends the correct reminder email via Gmail.
• Escalates 30+ to account managers: for 30+ day invoices, posts an alert to a Slack account-manager channel and logs a follow-up activity back on the invoice in Odoo.

Use cases

• Weekly A/R follow-up for SaaS finance teams who want consistent overdue reminders.
• Escalation workflows that move invoices from “reminder” to “account-manager attention” automatically at 30+ days.
• Ops visibility: finance gets a digest in Gmail and a snapshot in Slack.

Technical details

• Scheduler: runs every Monday at 9am (n8n schedule).
• Nodes / integrations: set, no op, odoo, gmail, slack, switch.
• Required setup: add an Odoo API credential with access to Accounting/Invoicing; ensure invoices exist in account.move with partner_id, due dates, and payment state populated.
• Gmail setup: configure finance/ops recipients (e.g., finance-team@yourcompany.com, ops-team@yourcompany.com) and email wording.
• Slack setup: set target channel IDs/names for the finance digest and the account-manager alerts.