Payment history (35%): The most important credit scoring fac..

Payment history (35%): The most important credit scoring factor, payment history takes into account whether you make on-time payments in full or have a history of late payments or delinquency.
Amounts owed (30%): This factor is made up of the total amount of debt you owe across your credit accounts, like on credit cards and loans, as well as your credit utilization rate (CUR), which is your total revolving debt divided by your total revolving credit limits.
Credit history (15%): This factor tracks the length of time you’ve had credit.
New credit (10%): This factor considers your recent credit inquiries and new credit accounts.
Credit mix (10%): This factor evaluates the different types of credit accounts you have open to see how you handle different credit products, like personal loans, credit cards, car loans, student loans and mortgages.

FICO® Score 9 vs. FICO® Score 8
As an update to the FICO® Score 8, the FICO® Score 9 differs in several ways to reflect current trends in consumer credit habits. Checking out the following key differences between these credit scoring models can help you understand why one of your scores may be different from the other.
Medical collections are treated differently than other collection types for FICO® Score 9
Medical collections are weighted differently than other collection accounts for FICO® Score 9. FICO® and the Consumer Financial Protection Bureau found that unpaid medical debt was less indicative of creditworthiness — your likelihood of paying back what you owe or credit risk. So unpaid medical debt now has less of a negative impact on credit score calculations than it did in previous versions.

While this is good news for borrowers who have had their unpaid medical bills accumulate into unpaid medical debt, this change only affects lending decisions or credit evaluations based on FICO® Score 9. If the lender uses a previous FICO® score version, like the FICO® Score 8, medical collections will be treated like any other type of collections accounts.[2], [4]

Rent payments are included in FICO® Score 9 calculation
Previous FICO® versions didn’t include rental history, or payment history for rent payments, in credit score calculations, although it was sometimes reflected on credit reports. FICO® Score 9 now takes rental payment history into account, which helps borrowers with little to no credit history as well as those who make on-time rent payments.

Making on-time payments through a third-party rental reporting company, like LevelCredit, or through a landlord who reports them to the major credit bureaus, may have a positive impact on your FICO® score as determined by the FICO® Score 9.[2]

Paid collections no longer have a negative impact on FICO® Score 9 calculations
If you’ve dealt with a collection agency, you may be encouraged to know that FICO® Score 9, does not factor paid collections into the credit score. So with FICO® Score 9, your score no longer feels the negative impact once your debt is paid in full.

On the other hand, FICO® Score 8 includes unpaid and paid collections accounts in credit score calculations, which can have a negative impact on your credit score after the collection debt has been paid off unless the amount is less than $100.[5]

FICO® Score 8 is the most used credit score model by lenders
FICO® Score 8 is still the most widely used credit scoring model[2], with 90%[6] of lenders using some version of FICO® and some using VantageScore.

You can check both your FICO® Score 8 and 9 and see the differences in your FICO® scores through FICO® Open Access.[7] Then you can get your free credit report to see what items may be making a difference between your scores.

You’re entitled to a free credit report once per year from each of the major credit bureaus, which you can access at AnnualCreditReport.com. You can also check your credit report for a fee any time you like with any of the three major credit bureaus (Experian, Equifax and TransUnion).

Understanding the differences between the newer and older versions helps you understand why your scores may differ. With your credit report, you can see what items FICO® is factoring into your scores and determine what you might adjust in your personal finances and credit habits to give your scores a positive impact.

Which credit score version do lenders use?
Lenders can choose which credit score they use when assessing applications. Not only might lenders use base credit scoring models, but they can also use industry-specific credit models. Lenders determine which score to use based on the credit product type and whether they want a more detailed credit risk prediction tailored to that specific type of credit.[2]

Some industry-specific FICO® scores include:

FICO® Auto Score: Lenders may use this score if you apply for an auto loan.
FICO® Bankcard Score: Credit card issuers may check this score if you apply for a credit card.
Base credit scoring models like FICO® Score 8 and FICO® Score 9 can be used by lenders for these credit products and a range of others. Lenders may check your FICO® score if you apply for a mortgage, personal loan, student loan, credit card or other credit accounts.[2]

How to check your FICO® score?
You can check your FICO® scores for free or through some credit card providers and FICO® Score Open Access[7], which works with credit card issuers and other financial institutions to give you free access to your credit scores.