{"product_id":"automate-overdue-invoice-emails-with-google-sheets-n8n","title":"Automate Overdue Invoice Emails with Google Sheets \u0026 n8n","description":"\u003ch3\u003eAutomatically escalate overdue invoices from Google Sheets—every day\u003c\/h3\u003e\n\u003cp\u003eThis n8n workflow checks your Google Sheets invoices daily, calculates how many days each pending invoice is overdue, sends the correct Spanish escalation email via SMTP, and then updates the sheet with the latest notice level and date.\u003c\/p\u003e\n\n\u003ch3\u003eWhat this workflow does\u003c\/h3\u003e\n\u003cul\u003e\n  \u003cli\u003e\n\u003cb\u003eRuns on a schedule:\u003c\/b\u003e it executes every day at \u003cb\u003e09:00 (Europe\/Madrid)\u003c\/b\u003e using an n8n Schedule Trigger.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cb\u003eReads invoice rows from Google Sheets:\u003c\/b\u003e it pulls invoice records from the configured spreadsheet (\u003ci\u003edocumentId\u003c\/i\u003e and \u003ci\u003esheetName\u003c\/i\u003e in both read and update steps).\u003c\/li\u003e\n  \u003cli\u003e\n\u003cb\u003eFilters and calculates overdue days:\u003c\/b\u003e it focuses on invoices where \u003cb\u003eestado=\"pendiente\"\u003c\/b\u003e, optionally skips weekends, and computes days overdue from \u003cb\u003evencimiento\u003c\/b\u003e.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cb\u003eChooses an escalation level:\u003c\/b\u003e it selects escalation thresholds at \u003cb\u003e7 \/ 21 \/ 45 days\u003c\/b\u003e overdue, but only if the escalation hasn’t been sent yet.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cb\u003eSends a Spanish email escalation:\u003c\/b\u003e it generates an email subject and body using templates for the selected level (including configurable company name and signature).\u003c\/li\u003e\n  \u003cli\u003e\n\u003cb\u003eSends via SMTP:\u003c\/b\u003e it delivers the email to the invoice contact using SMTP credentials and the configured \u003cb\u003efromEmail\u003c\/b\u003e.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cb\u003eUpdates Google Sheets after sending:\u003c\/b\u003e it matches invoices by \u003cb\u003enumero\u003c\/b\u003e and writes the latest \u003cb\u003enivel_aviso\u003c\/b\u003e and \u003cb\u003eultimo_aviso\u003c\/b\u003e date to the corresponding row.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eUse cases\u003c\/h3\u003e\n\u003cul\u003e\n  \u003cli\u003eReduce manual follow-ups by escalating unpaid invoices to customers automatically after 7\/21\/45 days.\u003c\/li\u003e\n  \u003cli\u003eKeep your accounts receivable process consistent across your team using a single Google Sheets source of truth.\u003c\/li\u003e\n  \u003cli\u003eOperate a lightweight SaaS billing reminder system without building a full custom portal.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eTechnical details\u003c\/h3\u003e\n\u003cul\u003e\n  \u003cli\u003e\n\u003cb\u003eIntegrations\/Nodes:\u003c\/b\u003e Schedule Trigger, Google Sheets (read + update), Code (calculation + template selection), Email send (SMTP), and supporting steps used in the workflow logic.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cb\u003eRequired sheet columns:\u003c\/b\u003e \u003cb\u003enumero\u003c\/b\u003e, \u003cb\u003ecliente\u003c\/b\u003e, \u003cb\u003eemail\u003c\/b\u003e, \u003cb\u003eimporte\u003c\/b\u003e, \u003cb\u003evencimiento\u003c\/b\u003e, \u003cb\u003eestado\u003c\/b\u003e, \u003cb\u003enivel_aviso\u003c\/b\u003e, \u003cb\u003eultimo_aviso\u003c\/b\u003e.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cb\u003eConfiguration:\u003c\/b\u003e Google OAuth2 credentials for reading\/updating; SMTP credential with correct domain \u003ci\u003efromEmail\u003c\/i\u003e; adjustable thresholds, weekend skipping, and Spanish email templates.\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"N8N Commerce","offers":[{"title":"Default Title","offer_id":45962072752307,"sku":"N8N-19198","price":14.99,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0749\/6279\/6723\/files\/8YsvtIBZlGm9upB5_gcCG_AZaLGA3h.png?v=1788599827","url":"https:\/\/buyflowscripts.com\/products\/automate-overdue-invoice-emails-with-google-sheets-n8n","provider":"N8N Commerce","version":"1.0","type":"link"}