When you take out a new loan or debt (car, home mortgage. credit card) the info hits your credit report pretty fast, usually no later than the end of that month. Your credit report and FICO score is comprised of several factors kept highly secret and mysterious by the reporting agencies (Equifax, Experian, Transunion) that devise and report them to potential lenders.
But essentially, they look at payment history, amount of debt vs. credit available (on credit cards for example), employment stability, home ownership, events and public records (delinquincies, bankruptcies, liens). The lender will also take into account your income.
Having taken on new debt certainly cannot help your credit score, but the good news is that a change in any one the areas mentioned above only changes the overall rating by the weight that it measures into the score.
Tip: your credit report is available, by law, once a year from the credit reporting agencies. Check out equifax.com, experian.com, or transunion.com. For a fee, you can get all 3 at once and your FICO score. You can view it immediatel online! Go check it out and make sure it's correct too-it has a tool for disputing any false info or debts you already paid but still showing up.
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