Your credit score is a three digit number that lenders use to help them decide on the probability that they will be paid back. The higher your scores, the more likely you are to get a loans and credit cards at the most favorable terms.
If your credit is not as good as you would like it, you are not the only one. Improving your scores takes time, but the sooner you address the issues that are causing your score to go down, the faster your score will go up. You can increase your scores by taking several steps, like a budget to pay your bills on time, paying down old accounts.
Most credit scoring models take into consideration your payment history, how much credit you regularly use, how old the accounts are, the types of accounts, and how often you have hard inquiries.
Here are a five steps to help you rebuild your credit.
1. Pay your bills on time.
When a lender checks your credit, they are interested in how reliably you pay your bills. Previous payment performance is usually a good way to predict future performance. You are able to positively influence this factor by paying all your bills on time, as agreed, each month. Late payments, or settling out for less than what you originally agreed to pay, can negatively impact your scores.
2.Pay off debt and keep your balance low on credit cards or other revolving credit.
The credit utilization ratio is calculated by adding all your credit card balances and dividing that amount by your credit limit. So, if you typically charge $2000 a month and you're total credit limit altogether is 10k, your utilization ratio is 20%.  
To determine your average credit utilization ratio, look at all your credit card statements from the last year. Add the balances for each month across all your cards and divide that by 12. That is how much credit you use on average each month. 
Lenders like to see low ratio's of 30% or less and people with the best scores often have very low credit utilization ratios. A low ratio tells lenders you have not maxed out your cards and seem to know how to manage well.  
3. Apply for new credit based accounts only as needed.
Dont just open up accounts to have more accounts on your credit, chances are it likely wont improve your credit. Uneeded credit can harm your score in a lot of ways. 
4. Dont close unused credit cards.
Keeping unused credit cards open (assuming they are not charging annual fees) is a smart idea because closing an account may increase your credit utilization ratio. Owing the same amount but having fewer open accounts may lower your credit scores.
5.Dispute any inaccuracies on your report.
You should check your scores with all three credit reporting bureaus (TransUnioin, Equifax, and experian (the source of this information) Incorrect information could be negatively impacting your score. Verify the accounts are correct, if they are not, dispute them.   
How long does it take to rebuild a credit score?
If you have negative information on your credit report, such as late payments, a public record item (bankruptcy) or too many inquiries, you should pay your bills and wait. There is no quick fix for bad credit scores.  
The length of time it takes to rebuild your credit history after a negative change depends on the reasons for the change. Most negative changes in credit scores are due to the addition of a negative element to your credit report, such as delinquency or collection account. These new elements will continue to effect your credit score until they reach a certain age.  

Delinquencies remain on your report for 7 years. 
Most public record items remain on your credit from 7-10 years.
Inquiries remain on your report for 2 years.
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