Gmail Receipt Parsing with Claude to Google Sheets Reconcile

Turn Gmail PDF receipts into a reconciled spreadsheet + Slack status—automatically

This n8n workflow watches your Gmail for PDF receipts, uses Anthropic Claude to extract structured data, saves validated results to Google Sheets, then matches receipts to a pasted card statement and posts a reconciliation summary to Slack.

What this workflow does

• Automatically monitors Gmail: Triggers every 15 minutes when an unread email with the label receipts arrives with a PDF attachment (or you can run the reconciliation flow manually).
• Processes PDFs one by one: Splits each email into one item per PDF attachment and extracts PDF text for verification.
• Extracts receipt fields with Claude: Sends each PDF to Anthropic Claude to extract receipt data as JSON, including vendor, date, currency, line items, tax, totals, and payment method.
• Validates before saving: Checks Claude output against the extracted PDF text and performs basic arithmetic validation. Problem cases are flagged as Needs review.
• Stores results in Google Sheets: Appends/updates receipt records in the Receipts tab.
• Reconciles against card lines: On manual reconciliation, reads Receipts and Card tabs, matches by amount within a configurable date window, and rebuilds the Matches tab.
• Alerts via Slack: Creates a short status summary of items needing attention and posts it to a selected Slack channel.

Use cases

• SaaS operators who need reliable, auditable receipt capture for monthly spend tracking.
• Automation engineers building a receipt-to-reconciliation pipeline using Google Sheets.
• Teams that want Slack notifications whenever receipt parsing or reconciliation needs review.

Technical details

• Triggers/logic: if, set, code
• Integrations: Gmail, Google Sheets (OAuth2), Anthropic (Claude), Slack
• Utilities: http request and workflow notes via sticky note

Set up Gmail, Google Sheets, Anthropic, and Slack credentials, initialize the Receipts, Card, and Matches tabs, and start reconciling receipt data with confidence.