{"product_id":"automate-overdue-invoice-chasing-n8n-google-sheets-openai-gmail-drafts","title":"Automate Overdue Invoice Chasing: n8n, Google Sheets, OpenAI \u0026 Gmail Drafts","description":"\u003ch3\u003eAutomate Overdue Invoice Chasing with n8n + Gmail Drafts (OpenAI-Assisted)\u003c\/h3\u003e\n\u003cp\u003eStop manually following up on late payments. This n8n workflow checks your \u003cstrong\u003eGoogle Sheets\u003c\/strong\u003e invoices every day at \u003cstrong\u003e9am\u003c\/strong\u003e, uses \u003cstrong\u003eOpenAI\u003c\/strong\u003e to generate an overdue reminder with an escalating tone, and creates a \u003cstrong\u003eGmail draft\u003c\/strong\u003e for each client—then logs the chase in your sheet.\u003c\/p\u003e\n\n\u003ch3\u003eWhat this workflow does\u003c\/h3\u003e\n\u003cul\u003e\n  \u003cli\u003e\n\u003cstrong\u003eRuns on a schedule\u003c\/strong\u003e every day at \u003cstrong\u003e9am\u003c\/strong\u003e (Schedule Trigger).\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eReads invoice rows\u003c\/strong\u003e from the \u003cstrong\u003e“Invoices”\u003c\/strong\u003e tab in Google Sheets.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eFilters for action\u003c\/strong\u003e: selects \u003cem\u003eunpaid\u003c\/em\u003e invoices that are \u003cem\u003epast due\u003c\/em\u003e and have \u003cem\u003enot\u003c\/em\u003e been chased in the \u003cstrong\u003elast three days\u003c\/strong\u003e.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eEscalates reminder tone\u003c\/strong\u003e by assigning a reminder tier (e.g., \u003cstrong\u003epolite\u003c\/strong\u003e, \u003cstrong\u003efirmer\u003c\/strong\u003e, or \u003cstrong\u003efinal\u003c\/strong\u003e) based on how many days the invoice is overdue.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eGenerates the email body with OpenAI\u003c\/strong\u003e using the invoice details and tier instructions.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eCreates Gmail drafts\u003c\/strong\u003e addressed to the client. For \u003cstrong\u003efinal notices\u003c\/strong\u003e, it appends the \u003cstrong\u003epayment link\u003c\/strong\u003e from the sheet.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eUpdates Google Sheets\u003c\/strong\u003e: sets \u003cstrong\u003e“Last chased”\u003c\/strong\u003e to the current timestamp for the matched invoice row.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eUse cases\u003c\/h3\u003e\n\u003cul\u003e\n  \u003cli\u003e\n\u003cstrong\u003eSaaS operations\u003c\/strong\u003e teams that invoice monthly and want consistent overdue follow-ups without daily manual effort.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eFreelancers\/consultancies\u003c\/strong\u003e using Google Sheets as their billing source of truth and needing client-friendly reminders.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003en8n automation engineers\u003c\/strong\u003e who want an invoice chasing pattern combining Sheets tracking + OpenAI drafting + Gmail review.\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eTechnical details\u003c\/h3\u003e\n\u003cul\u003e\n  \u003cli\u003e\n\u003cstrong\u003eGoogle Sheets\u003c\/strong\u003e: read from and update the \u003cstrong\u003eInvoices\u003c\/strong\u003e tab (columns required include Invoice #, Client, Client email, Due, Amount, Status, Payment link, Last chased).\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eGmail\u003c\/strong\u003e: creates the reminder as a `draft` message to the client.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eOpenAI\u003c\/strong\u003e: drafts a short reminder email body with tier-appropriate tone.\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eSchedule Trigger\u003c\/strong\u003e: runs daily at 9am; uses \u003cstrong\u003ecode\u003c\/strong\u003e logic to filter and assign tiers.\u003c\/li\u003e\n  \u003cli\u003eInvoices marked \u003cstrong\u003eStatus = PAID\u003c\/strong\u003e are excluded.\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"N8N Commerce","offers":[{"title":"Default Title","offer_id":46086645219507,"sku":"N8N-19916","price":38.99,"currency_code":"GBP","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0749\/6279\/6723\/files\/Ya_JkI3mc7r9h8322ET6I_9zRvKuG1.png?v=1790327129","url":"https:\/\/buyflowscripts.com\/products\/automate-overdue-invoice-chasing-n8n-google-sheets-openai-gmail-drafts","provider":"N8N Commerce","version":"1.0","type":"link"}