Restflow.io

## Introduction

Duplicate leads in a Customer Relationship Management (CRM) system are a common challenge for sales teams in startups and growing companies. They clutter the database, inflate lead counts, confuse sales strategies, and reduce productivity. Manually cleaning duplicates is time-consuming and prone to human error.

This article presents a practical, step-by-step guide to automate the detection and removal of duplicate leads from your CRM using n8n — a powerful, open-source workflow automation tool. This automation benefits sales operations teams by ensuring lead data integrity, improving reporting accuracy, and freeing up time to focus on closing deals.

### Tools and Services Integrated

– **n8n**: An automation and workflow orchestration platform.
– **CRM API (e.g., HubSpot, Salesforce, Pipedrive)**: To fetch, identify, and delete/update duplicate leads. We’ll use HubSpot as an example, but this method can be adapted to other CRM platforms with API access.
– **Google Sheets (optional)**: For logging duplicates or additional manual review.

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## Automation Use Case Overview

**Problem**: Duplicate leads reduce data quality in CRM, causing wasted outreach and inaccurate sales reports.

**Who benefits**: Sales operations teams, CRM administrators, sales managers.

**Solution**: An automated, scheduled workflow that:

1. Fetches leads from the CRM.
2. Identifies duplicates based on predefined criteria (e.g., matching email addresses).
3. Removes or merges duplicates via CRM API calls.
4. Optionally logs duplicate info to Google Sheets.

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## Step-by-Step Technical Tutorial

### Prerequisites

– An n8n instance set up (cloud-hosted or self-managed).
– API credentials and OAuth access tokens for your CRM.
– Basic familiarity with n8n nodes, JSON, and API requests.

### Step 1: Define Duplicate Criteria

Typically, email address is the most reliable unique key for leads. Alternatively, you may combine:
– Full name + company
– Phone number + email

For this tutorial, we focus on duplicates identified by identical email addresses.

### Step 2: Create the Workflow in n8n

#### 1. Trigger Node: Schedule Trigger

– Add a **Cron** node to run the workflow at regular intervals (e.g., daily at midnight).
– This ensures the CRM leads data is regularly scanned for duplicates.

#### 2. CRM API: Fetch Leads

– Use the **HTTP Request** node or a dedicated CRM node (e.g., HubSpot node).
– Configure it to fetch all leads or contacts from the CRM.
– Parameters:
– Endpoint: `/contacts/v1/lists/all/contacts/all` (HubSpot example)
– Pagination: Handle multiple pages if your lead count exceeds API limits.
– Output: JSON array containing all lead records.

#### 3. Identify Duplicate Emails

– Use the **Function** node to process the leads array and detect duplicates.
– Logic:
– Extract emails from all leads.
– Store emails in a dictionary with counts.
– Identify emails appearing more than once.
– Collect all lead objects matching these duplicate emails.

##### Sample Code for Function Node
“`javascript
const leads = items.map(item => item.json);
const emailCounts = {};

leads.forEach(lead => {
const email = lead.properties.email ? lead.properties.email.value.toLowerCase() : null;
if(email) {
emailCounts[email] = (emailCounts[email] || 0) + 1;
}
});

const duplicateEmails = Object.keys(emailCounts).filter(email => emailCounts[email] > 1);

const duplicates = [];

leads.forEach(lead => {
const email = lead.properties.email ? lead.properties.email.value.toLowerCase() : null;
if(duplicateEmails.includes(email)) {
duplicates.push({ json: lead });
}
});

return duplicates;
“`

#### 4. Group Duplicates by Email

– Use the **SplitInBatches** node to process duplicates batch by batch or the **GroupBy** operation via a custom function to group leads by email.

#### 5. Decision Logic: Choose Which Duplicate to Keep

– Typically, you keep the most recently updated or enriched lead.
– Implement logic to:
– Sort duplicates by the `lastmodifieddate` or `createdate` field.
– Keep the lead with the most recent timestamp.
– Identify others as duplicates to be deleted or merged.

Sample Function Logic
“`javascript
const grouped = {};
items.forEach(item => {
const email = item.json.properties.email.value.toLowerCase();
if(!grouped[email]) grouped[email] = [];
grouped[email].push(item.json);
});

const results = [];

for(const email in grouped) {
const leads = grouped[email];
leads.sort((a,b) => new Date(b.properties.lastmodifieddate.value) – new Date(a.properties.lastmodifieddate.value));

// Keep first lead
// Leads from second onwards flagged for deletion
const toKeep = leads[0];
const toDelete = leads.slice(1);

toDelete.forEach(lead => {
results.push({ json: { keepId: toKeep.id, deleteId: lead.id, email }});
});
}

return results;
“`

#### 6. Delete Duplicate Leads via CRM API

– Use the **HTTP Request** node to send DELETE requests for each duplicate’s lead ID.
– Parameters:
– Endpoint: `/contacts/v1/contact/vid/:vid/profile` (HubSpot example)
– HTTP Method: DELETE
– Loop over each duplicate from the previous step.

#### 7. (Optional) Log Deleted Duplicates to Google Sheets

– Connect a **Google Sheets** node to append rows with deleted lead IDs and emails.
– Useful for audit trails and manual review.

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## Step 3: Error Handling and Optimization Tips

– **API Rate Limits**: Respect your CRM’s API rate limits by implementing delays or batching.
– **Pagination**: Always handle pagination rigorously — many CRM APIs limit records per call.
– **Data Validation**: Check for leads without emails to avoid false positives.
– **Retries**: Add retry mechanisms on failed HTTP requests.
– **Logging**: Incorporate logs of actions, including failures, for monitoring.
– **Security**: Store API credentials securely in n8n credentials manager.

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## Step 4: Scaling and Adapting the Workflow

– **Custom Duplicate Criteria**: Modify the identification function to include fuzzy matching, phone numbers, or company names.
– **Merge Instead of Delete**: Extend logic to merge lead data via CRM API instead of deleting, preserving valuable information.
– **Multiple CRMs**: Clone and adapt the workflow for other CRM platforms by updating API endpoints and authentication.
– **Real-Time Deduplication**: Trigger workflow on lead creation events via webhooks for immediate duplicate checks.

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## Summary

Automating duplicate lead removal with n8n saves sales teams from the tedious and error-prone task of manual database cleaning. Using n8n’s flexible nodes combined with API endpoints from your CRM, you can create a scalable, scheduled workflow that identifies duplicates by email, deletes the unwanted leads, and optionally logs the changes for audit.

By following the detailed steps in this guide, technical teams can implement a reliable automation, improving lead data quality and boosting sales efficiency.

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## Bonus Tip: Enhancing Data Quality with Enrichment

Integrate data enrichment services (e.g., Clearbit or Hunter) in your workflow before duplicate removal. By enriching leads with additional information, you can create more sophisticated duplicate detection rules based on multiple IDs or company data, yielding better targeting for the sales team.

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Feel free to customize the workflow according to your CRM API and organizational policies. Automation is a powerful ally for scaling revenue operations with accuracy and speed.