Do closed accounts affect credit score?

Closed accounts aren't deleted from your credit bureau till 6 years has passed. All it will show is that the balance is nil and the DLA (date of last activity) will show what month/yr, you had a nil balance on your statement. If you close all your old credit cards and keep your new ones, that might not be good either because the age of your credit cards are part of your score. it's best to keep and maintain your old credit cards and get rid of any unused new credit cards.

Things to think about re:credit score is: maintaining good long established credit history, making sure your balances are low and not using more than 30% of your line of credit, and reducing the number of credit cards you have. My suggestion is to have 2 credit cards (one visa and one m/c) and maybe 1 extra card for emergencies only (make sure you use the emergency credit card every 6 months so it not considered inactive). This will help, so you don't have so many bills and you keep track of your purchases. And lastly, pay your bills in full and on time so that you're not charged the daily interest.