HighLevel Contact Address Verification using Lob API - n8n Workflow

• CRM Administrators and Sales Operations teams managing HighLevel.


• Users running direct mail campaigns who need high address accuracy.


• Businesses looking for reliable data validation n8n templates.


• Developers needing a scalable, pre-built address verification n8n node implementation.

Maintaining accurate and deliverable mailing addresses is crucial for any business running physical campaigns. This essential n8n workflow solves the common problem of unreliable contact data by integrating your HighLevel CRM with the industrial-grade Lob address verification API.

By leveraging this specific n8n automation, every time a new contact is created, their address is instantly validated. This not only prevents unnecessary costs associated with failed mailings but also ensures your CRM database remains clean and trustworthy. This n8n workflow provides a rapid, automated validation layer, triggering downstream actions based on verification success or failure.

This automation is initiated by an incoming webhook from your CRM (such as HighLevel) whenever a new contact is created or updated with address information. This setup utilizes a powerful series of n8n nodes for sequential data processing and decision-making:

1. Trigger Reception: The CRM Webhook Trigger n8n trigger waits for data (including contact address, city, state, and zip code) from the CRM.


2. Data Standardization: The Set Address Fields n8n node standardizes the incoming payload to match the required parameters for the Lob API.


3. Address Verification: The core of this process is the Address Verification n8n node (an HTTP Request), which sends the address payload to the Lob API's /v1/us_verifications endpoint. This step requires your configured Lob API keys for Basic Authentication.


4. Decision Routing: The Switch n8n node evaluates the response from Lob, specifically checking the deliverability status field.


5. Success Path: If the address is confirmed as 'deliverable,' the data flows to the Update HighLevel - Deliverable n8n node, which applies a 'Mailing Address Deliverable' tag to the contact in HighLevel.


6. Failure Path: If the address is 'NOT deliverable,' the workflow follows the alternate route to the Update HighLevel - NOT Deliverable n8n node, tagging the contact for manual review (e.g., 'Mailing Address NOT Deliverable'). This entire n8n workflow ensures complete end-to-end data integrity.

To use this powerful n8n workflow template, follow these steps:

1. Import: Copy the provided JSON code and import it directly into your n8n instance.


2. HighLevel Credentials: Configure the Update HighLevel - Deliverable and Update HighLevel - NOT Deliverable n8n nodes with your HighLevel API credentials.


3. Lob Setup: Create an account at Lob.com and generate an API Key. This key is used for Basic Authentication.


4. API Node Configuration: Update the Address Verification n8n node (HTTP Request) to include the Basic Authentication using your Lob API credentials.


5. Webhook Setup: Activate the CRM Webhook Trigger n8n node and copy the unique webhook URL. Paste this URL into your HighLevel automation settings to trigger this n8n workflow whenever a new contact is created or an address is added.


6. Testing: Execute a test run by creating a new contact in HighLevel to ensure the n8n trigger fires correctly and the address verification works as expected.

CRM Webhook Trigger (n8n trigger):
Function: Starts the n8n workflow upon receiving a POST request, typically from HighLevel or another CRM when a new contact is created.
Key Configuration: Uses a unique path to listen for incoming contact data.
Set Address Fields (n8n node):
Function: Prepares and standardizes the webhook data, mapping fields like address, city, state, and zipcode for the subsequent API call.
Address Verification (HTTP Request n8n node):
Function: Sends the standardized address data to the Lob API endpoint for official deliverability verification.
Key Configuration: Configured as a POST request to https://api.lob.com/v1/usverifications and requires Basic Authentication using the Lob API key.
Switch (n8n node):
Function: Routes the workflow based on the deliverability status returned by the Lob API (i.e., 'deliverable' vs. anything else).
Update HighLevel - Deliverable (HighLevel n8n node):
Function: If the address is valid, it updates the HighLevel contact, applying the 'Mailing Address Deliverable' tag.
Update HighLevel - NOT Deliverable (HighLevel n8n node):
Function: If the address is invalid, it applies the 'Mailing Address NOT Deliverable' tag, initiating follow-up procedures outside this n8n workflow.