It’s easy to complete a balance transfer and forget to close the original card account.  In some cases, you’ll want to keep the first account open.  In other cases, it will be beneficial to close it.

Having too many credit lines open could make you look riskier in the eyes of lenders.  They might be concerned that you will overextend yourself.

In addition, if you have many accounts open simultaneously, there’s a greater chance that you will forget about an account with a small balance and unintentionally stop making payments on it.

Ideally, you should keep at least 2 or 3 accounts and use all of them moderately, as otherwise, it will be hard for you to build and maintain a positive credit history and it will be hard for lenders to assess your creditworthiness. 

It’s also important to understand that once you close an account, the record of the closed account remains on your credit report.  Closing unused credit accounts may cause your credit score to drop in the short term, as you will have higher balances relative to total available credit.

 Therefore, it’s important to strike the right balance, whereby you have enough credit lines open, with moderate and responsible use to both build your positive credit history and ensure you have adequate credit available relative to the amount of credit in use.