Remove Duplicates from Contractor and Tradesperson Data
✓ TestedWorks with CSV, Excel, Google Sheets → JSON-LD Schema
By dataclean.to team · 2026-02-12
Contractor databases grow duplicate-heavy because tradespeople often operate under both a personal name and a business name, hold licenses in multiple jurisdictions, and appear in vendor lists from different projects over the years. A plumber might be listed as 'Mike Johnson Plumbing', 'M&J Plumbing LLC', and 'Michael Johnson' across your vendor database, each with different phone numbers from different periods. dataclean.to matches contractor records by comparing license numbers, phone numbers, addresses, and name variations to unify fragmented vendor profiles.
The Problem
Duplicate contractor records create compliance and payment headaches. When a contractor's insurance certificate is on file under one profile but their payment history is under another, project managers cannot quickly verify that the contractor is currently insured before allowing them on site. Accounts payable may issue 1099s to the wrong entity or split payments across profiles, creating tax reporting discrepancies. Prequalification databases with duplicates fail to aggregate a contractor's complete project history, making it difficult to evaluate whether they have sufficient experience for a new project. W3C Data on the Web Best Practices
How to Fix It
1
Export contractor and vendor records
Pull data from your vendor management system, project records, and accounting software. Include business name, owner name, license number, trade specialty, phone, email, address, insurance expiration, and W-9 information.
2
Upload to dataclean.to
Upload the CSV. The tool normalizes business names, matches license numbers across jurisdictions, and compares contact details to identify contractors who appear under multiple entries.
3
Review duplicate contractor clusters
Examine groups of records that likely represent the same contractor. The tool shows relationships between a personal name entry and a business name entry that share the same phone number, or entries with the same license number under different business names.
4
Merge into unified contractor profiles
Consolidate confirmed duplicates into one vendor record per contractor. All license numbers, insurance certificates, project histories, and payment records are combined into the master profile.
5
Export the clean vendor database
Download the deduplicated CSV and update your vendor management system. Each contractor now has one profile with their complete qualifications, project history, and current compliance documents.
Frequently Asked Questions
How does the tool handle contractors who changed their business name?
Records with different business names but the same owner name, phone number, or license number are flagged as potential duplicates. The merged profile retains both names with the current business name as primary, preserving the historical project record under the old name.
Can it match contractors across different trade categories?
Yes. A contractor who holds both an electrical and a general contractor license may appear under different trade categories. The tool matches on contact details and license numbers regardless of trade classification.
What about sole proprietors versus their LLC entity?
The tool flags records where a personal name and an LLC name share the same address, phone, or license number. You can merge these into one profile that shows both the individual and business entity information for tax and compliance purposes.
Example: Input → Output
name
job_title
email
phone
org
Jane Smith
Marketing Manager
jane@example.com
+1 (555) 123-4567
Acme Corp
john doe
developer
JOHN@EXAMPLE.COM
555.987.6543
acme corp
Red rows show common data quality issues. dataclean.to normalizes and generates JSON-LD automatically.