One of the top credit mistakes would be:

Closing Credit Cards Accounts

Some of you may wonder why Closing Credit Cards is number one on this list as the biggest credit mistake even above Missing Payments. Closing credit card accounts will not increase your credit scores. There are two huge reasons not to close credit cards that you no longer use. They are:

• They will eventually fall off your credit reports - In most cases credit information will remain on your credit files for no longer than seven years from the account's Date of Last Activity or "DLA." Your DLA will continue to update each month so long as the account remains open. So, an open account will never reach the seven-year mark because each month your DLA updates to the current month. However, once you close the account your DLA will cease to update and the clock begins ticking. Eventually the account will be removed permanently from your credit reports. Why is this a bad thing? The answer to this one is very simple. It's all about your impressive past.  If you have a perfect record of making your payments on time then this significantly helps your credit scores so why would you ever want that history to disappear? You wouldn't. What should you do with old credit cards that you don't use any longer? Use the card once every few months for dinner or a low dollar item. Pay the bill in full. Doing this will ensure that the account will never be closed and you'll always get credit for your good payment history.
• You will hurt your "utilization" measurements - This is significantly more important than your closed accounts eventually falling off your credit reports. Revolving Utilization is the amount of your revolving credit card limits that you are currently making use of. For example, if you have an open credit card with a $2,000 credit limit and a $1,000 balance then you are 50% "utilized" on that account because you're using half of the credit limit. This measurement is almost as important to your credit scores as making your payments on time. If you had a second open, but unused, credit card with a $2000 credit limit and a $0 balance then your aggregate revolving utilization is 25% because you have $4000 in credit limits and $1000 in balances. $1000 divided by $4000 is .25 or 25%. How will closing an unused credit card hurt your credit score? Let's say that you closed that second unused credit card from the above example. Once you do so then you remove it from any utilization calculation and now you're stuck with one open card with a $2000 credit limit and a $1000 balance. Now your utilization has gone from 25% to 50% (divide $1000 by $2000 and you get .50 or 50%). As this percentage increases, your credit score decreases.

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More to come on Top Credit Mistakes!