Automate Monthly Finance Reports with n8n: Google Sheets + GPT-4 + Gmail

Input: Google Sheets transaction records → Process: n8n filters last-month data and GPT-4 generates insights → Output: Automated Gmail report

Who

Small businesses, startup founders, or e-commerce operators who need regular financial summaries without a dedicated finance team

You get

A scheduled monthly email report with income, expenses, and AI-generated financial insights

You need

n8n · google-sheets · openai · gmail · schedule

Steps

1. Import the Workflow JSON

   In n8n, create a new workflow, click the '...' (More Options) icon in the top right, select 'Import from JSON', and paste the provided workflow JSON.

2. Configure Credentials and the Google Sheets Node

   Open the '1. Get Finance Transactions (Google Sheets)' node: under Authentication, select or create a Google Sheets OAuth2 credential; replace the Sheet ID with your actual Google Sheet ID; the default range is FinanceSummary!A:E—update the range if your sheet name differs.

3. Configure the OpenAI Node

   Open the '3. Generate AI Financial Insights' node: select or create an OpenAI API Key credential; the model is already set to gpt-4. The prompt (source original, do not alter punctuation or variable names) is:

   Execution prompt · Source text。Prompt field of the OpenAI node

   Copy prompt

   You are a finance assistant. Analyze the following transaction data. Calculate the total income and total expense for the period. Then, provide 3 concise bullet-point financial insights based on the data. Structure your output clearly:
   
   Total Income: [Amount]
   Total Expense: [Amount]
   Key Insights:
   - [Insight 1]
   - [Insight 2]
   - [Insight 3]
   
   Transactions:
   {{JSON.stringify($json, null, 2)}}

4. Configure the Gmail Node and Email Details

   Open the '4. Send Monthly Finance Report Email' node: select or create a Gmail OAuth2 credential; replace the sender and recipient emails; adjust the subject if needed.

5. Add and Configure the Schedule Trigger, Then Activate

   Add a Schedule Trigger (or Cron) node at the start of the workflow, set Mode to 'Every Month' on day 1, and connect it to the Google Sheets node. Save the workflow and toggle from Inactive to Active.

You are setting up an n8n automation workflow: read transaction data from Google Sheets monthly, filter last month's records, call GPT-4 to generate an income/expense/insights summary, and send the report via Gmail. First confirm you have access to an n8n instance plus Google Sheets OAuth2, OpenAI API Key, and Gmail OAuth2 credentials, then import the JSON and configure each node step by step.