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The Motley Fool has good information on how the FICO is calculated. They generally indicate that such a pattern would drop your FICO score anwhere from 20 to 80 points (or maybe more depending how many credit cards you apply for), as lenders would see this as an indication that you are trying to run up your available credit. Closing those accounts will not instantly restore your credit. In fact, if you have debt elsewhere, closing those credit cards could actually hurt your credit score, as your ratio of debt to available credit would increase.