## Introduction
Duplicate leads are a common pain point for sales and marketing teams, leading to wasted effort, skewed analytics, and reduced customer experience quality. HubSpot’s native Duplicate Check feature helps mitigate this by preventing the creation of duplicate contacts and companies based on customizable filters. However, HubSpot’s paid tiers that include this robust feature can increase operational costs significantly for startups or small teams.
In this tutorial, we will build an equivalent Duplicate Lead Checker automation using n8n — a powerful open-source workflow automation tool. By integrating your CRM, lead sources, and n8n, you can implement cost-effective, customizable duplicate detection logic tailored precisely to your data and business rules. This approach benefits startup CTOs and automation engineers looking to maintain data hygiene without the additional SaaS expense.
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## Overview of the Workflow
### Problem Addressed
The automation prevents creation and insertion of duplicate leads into the CRM (e.g., HubSpot, Pipedrive, or any custom database) by checking incoming lead details against existing leads using custom filters such as email, phone number, or company name.
### Tools/Services Used
– **n8n:** automation platform orchestrating the workflow
– **Lead Source(s):** could be a web form, a lead generation tool, or email intake (example uses Gmail trigger)
– **CRM API:** HubSpot API (can adapt to others) to query leads and create new leads
### Workflow Summary
1. Trigger: New lead arrives (e.g., email or webhook)
2. Extract lead data (email, phone, company)
3. Query the CRM via API to check if a lead with matching criteria already exists
4. If duplicate found, log or notify the responsible user/team
5. If no duplicates, create the new lead in CRM
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## Step-by-Step Technical Tutorial
### Prerequisites
– n8n installed and running (cloud or self-hosted)
– Access to your CRM API credentials (HubSpot API key or OAuth token)
– Lead ingestion method (e.g., Gmail access or incoming webhook)
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### Step 1: Setting Up the Trigger Node
**Goal:** Capture new leads as they arrive.
1. Add a trigger node depending on your lead source. For example, use the **Gmail Trigger** if leads come from email inquiries:
– Configure to watch for new emails in a specific label/folder.
– Extract relevant data from the email body or attachments.
Alternatively, if your leads come from a web form or another tool, use a **Webhook Trigger** exposing an endpoint for lead submissions.
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### Step 2: Parsing and Extracting Lead Fields
**Goal:** Extract key details (email, phone, company) for duplicate checking.
1. Add a **Set Node** or **Function Node** to parse the incoming data.
2. Spot and extract relevant information such as:
– `email`
– `phone`
– `companyName`
This may involve parsing JSON payloads, splitting text, or regex extraction in Function Nodes.
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### Step 3: Search for Duplicates in CRM
**Goal:** Query the CRM to see if a lead with matching parameters already exists.
1. Add an HTTP Request node configured to call your CRM’s search API.
For HubSpot:
– Use the [Get Contacts API](https://developers.hubspot.com/docs/api/crm/contacts) with search parameters.
– Example: querying contacts by email:
“`http
GET /crm/v3/objects/contacts/search
Content-Type: application/json
Authorization: Bearer {{API_TOKEN}}
{
“filterGroups”: [
{
“filters”: [
{
“propertyName”: “email”,
“operator”: “EQ”,
“value”: “{{email}}”
}
]
}
],
“properties”: [“email”, “phone”, “company”]
}
“`
2. Bind `{{email}}` dynamically from previous node data.
3. If your duplicate criteria include multiple fields, construct filters accordingly (email OR phone).
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### Step 4: Conditional Check on Search Results
**Goal:** Determine if the lead already exists.
1. Add an **IF Node** to check if the HTTP Request Node returned any matching contacts.
2. Logical condition:
– If result count > 0, a duplicate exists.
– Else, no duplicates found.
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### Step 5a: Handling Duplicates
**Goal:** Notify sales or log event.
1. If duplicate found, add a **Slack Node** or **Email Node** to notify relevant users.
2. Include details about the incoming lead and the existing duplicate.
3. Alternatively, write to a Google Sheet for auditing duplicates.
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### Step 5b: Creating New Lead if No Duplicate
**Goal:** Insert the new lead into the CRM.
1. Use the CRM’s Create Contact API (e.g., HubSpot’s Create Contact endpoint).
2. Provide extracted lead details as the payload.
3. Confirm the lead creation and optionally send a confirmation notification.
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### Step 6: Error Handling and Robustness Tips
– **API Rate Limits:** Implement retry logic in HTTP Request nodes to handle 429 errors or transient failures.
– **Data Validation:** Use Function Nodes to validate and sanitize input data before querying or creating leads.
– **Fallback Matching:** Use multiple filters (email fallback to phone or name) to catch duplicates more holistically.
– **Logging:** Save error and operation logs to an external system (e.g., Google Sheets, Datadog) for monitoring.
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## Scaling and Adaptation
– Add multiple lead sources by cloning the trigger node and merging data.
– Expand duplicate logic to handle company records or related entities.
– Integrate with other communication channels for notifications (MS Teams, SMS).
– Modularize the workflow using n8n sub-workflows to reuse duplicate checking logic in different contexts.
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## Summary
By using n8n to build a custom duplicate lead checker, startups and automation engineers can fully control the logic used to maintain lead data integrity without incurring additional SaaS costs. This modular, API-driven approach allows for flexible customization, easier adaption to varying data sources, and integration with existing tools like Slack and Google Sheets.
**Bonus Tip:** Combine this duplicate checking workflow with lead enrichment services (e.g., Clearbit API) in n8n to automatically append rich data to verified leads, streamlining prospecting further within your automation stack.