n8n Workflow: Validate Phone Numbers in Google Sheets (1Lookup)

Validate Phone Numbers in Google Sheets automatically—using 1Lookup (n8n Workflow: “Validate Phone Numbers in Google Sheets (1Lookup)”)

This n8n workflow runs hourly to read leads from your Google Sheets, validate each unprocessed phone number with 1Lookup, and write back the results—status, line type, DNC flag, recommended action, and a timestamp.

What this workflow does

• Runs every hour via a Schedule Trigger.
• Reads lead rows from a Google Sheets worksheet and uses a configured phone column name (default: Phone) to fetch the phone number.
• Skips already-checked entries by filtering out rows where the phone value is empty or where phone_status already exists.
• Validates each phone number using the 1Lookup community node (@momentum-labs/n8n-nodes-1lookup), continuing even if a lookup fails.
• Prepares update fields:
  • phone_status (or ERROR on failure)
  • line_type
  • dnc_listed
  • action
  • checked_at timestamp
• Updates the original row in Google Sheets by matching on row_number, so only the validation columns change.

Use cases

• Ensure your marketing or sales lead pipeline has up-to-date, validated contact numbers in Google Sheets.
• Run recurring n8n phone number validation so new rows are automatically checked without manual review.
• Use the returned dnc_listed flag and action to support compliance-oriented workflows.

Technical details

• Integrations/nodes: Schedule Trigger, Google Sheets, @momentum-labs/n8n-nodes-1lookup (1Lookup community node), plus supporting nodes like Set/Filter/Sticky Note.
• Setup requirements: Configure Google Sheets credentials and select the spreadsheet + sheet tab in both Google Sheets nodes.
• Schema expectations: Your sheet must include row_number and columns for phone_status, line_type, dnc_listed, action, and checked_at.
• Customization: Update phone_column in the Settings step if your phone field isn’t named Phone.