Credit Bureaus Explained: Equifax, Experian, and TransUnion

The three major credit bureaus—Equifax, Experian, and TransUnion—are private, for-profit companies that collect and sell your credit information. Understanding how they work is essential for managing your credit effectively.

What Credit Bureaus Do

Credit bureaus:

• Collect data from creditors about your accounts and payments
• Compile this data into credit reports
• Calculate credit scores based on the data
• Sell access to your credit information to lenders, landlords, employers, and insurers

They don't make lending decisions—they just provide the data that others use to make decisions.

The Big Three Bureaus

Equifax

• Founded: 1899
• Headquarters: Atlanta, Georgia
• Data breach: Yes, in 2017 (143 million consumers affected)
• Proprietary score: Equifax Beacon Score
• Notable: Often used for mortgage lending

Experian

• Founded: 1980
• Headquarters: Dublin, Ireland (US operations in Costa Mesa, CA)
• Largest bureau globally
• Proprietary score: Experian PLUS Score
• Notable: Offers Experian Boost feature to add utility/phone bills to your report

TransUnion

• Founded: 1968
• Headquarters: Chicago, Illinois
• Proprietary score: TransUnion TransRisk Score
• Notable: Often shows different data than the other two bureaus

Why Your Scores Differ Across Bureaus

Your credit scores from each bureau are often different because:

• Not all creditors report to all three bureaus: Some only report to one or two
• Different calculation methods: Each uses slightly different algorithms
• Timing differences: Creditors may report to bureaus on different days
• Errors: One bureau may have inaccurate information the others don't

It's normal for scores to vary by 20-30 points across bureaus.

Which Bureau Do Lenders Check?

It depends on the type of credit:

• Mortgages: Usually pull all three and use the middle score
• Auto loans: Often Experian or Equifax
• Credit cards: Varies by issuer, often TransUnion or Experian
• Personal loans: Usually one or two bureaus

How to Get Your Credit Reports

AnnualCreditReport.com (Free)

By federal law, you're entitled to one free report from each bureau every 12 months through AnnualCreditReport.com. This is the only truly free source authorized by the Federal Trade Commission.

Directly from Bureaus (May Cost Money)

• Equifax: equifax.com
• Experian: experian.com
• TransUnion: transunion.com
Note: These sites often try to upsell you on credit monitoring services.

Disputing Errors with Each Bureau

You must dispute errors separately with each bureau where they appear. All three accept disputes:

• Online (fastest, but hard to track)
• By mail (recommended—use certified mail with return receipt)
• By phone (may not be thoroughly documented)

Bureau Contact Information

Equifax

Disputes: P.O. Box 740256, Atlanta, GA 30374
Phone: 800-685-1111
Website: equifax.com/personal/credit-report-services

Experian

Disputes: P.O. Box 4500, Allen, TX 75013
Phone: 888-397-3742
Website: experian.com/disputes

TransUnion

Disputes: P.O. Box 2000, Chester, PA 19016
Phone: 800-916-8800
Website: transunion.com/credit-disputes

Streamline Your Credit Repair

Instead of manually creating three separate dispute letters for each item, use OriumAI to automatically generate FCRA-compliant letters for all three bureaus with one click. Our AI ensures each letter cites the right violations and legal sections for maximum effectiveness.