Most free credit score sites use what is called the VantageScore model to pull your credit score. The VantageScore model is similar to, but different and less precise than, the FICO credit score model used by banks when you apply for a mortgage. The scores provide by these free sites are sometimes called "educational scores" because they provide one version of your credit score rather than your precise FICO score, although the two versions should directionally similar. This does not mean that free credit score sites are inaccurate or not helpful, just that they provide a more directional assessment of your credit profile. In fact, we frequently recommend that borrowers use sites like CreditKarma, Credit Sesame or Credit.com because they allow you to monitor your credit scores for free and identify major issues with your credit profile without hurting your credit score, which is a valuable service.
The different credit scores you are seeing between the different free credit score services could be due to timing or because the services pull credit scores from different credit bureaus. Your credit score can vary across the different credit bureaus because they may access different credit account information or use different scoring methodologies. For example, I have an old debt that appears on my credit report for one of the credit bureaus but not the other two, so my score is different for that credit bureau. That is why it is important that borrowers understand their credit profiles for all three credit bureaus.
Rather than focusing on the different scores between the free credit score services, use them to track the progress you are making on improving your score. Additionally, you may want to check out AnnualCreditReport.com, which is another free service that enables you to check your credit report (not just your credit score) free, once a year. Reviewing your credit report should provide you with much more detailed information on your credit profile and better position you to take steps to improve your credit score. For example, you may have a debt account in collection that appears on your credit report that you are not aware of.
Moving ahead to when you apply for your mortgage, it is important to understand that lenders pull your FICO score from the three major credit bureaus -- Experian, Equifax and TransUnion -- and typically use the middle score to determine your ability to qualify for a mortgage. Additionally, if you are applying for a mortgage with a co-borrower, lenders typically use the lower score among both borrowers. We provide a comprehensive overview of your credit score and the mortgage process as well as a helpful explanation of how to improve your credit score before you apply for a mortgage that you can review.
I recommend that you review these resources on FREEandCLEAR and then continue to use the free credit score services to track your progress over time. Taking these steps combined with making sound financial decisions should position you to qualify for a mortgage in the future.