Closing a Long Time Open Credit Card and Credit Score

[kddrye1201]

I have a credit card that has been open since approximately 2009. It is paid off. I’m charged an annual fee. Because the card began as Orchard Bank and the bank moved accounts to Capital One, I have been told by Capital One they are required to bill the annual charge because that was the terms when they got the account. They also said they could not change the card to a different one without an annual fee unless I cancel the account. 
I don’t intend on using the card anymore but don’t want to pay an annual fee because it’s open. 
How will closing the account affect my credit score?

[LitaLou]

Closing the account will affect the "average age of revolving accounts." One factor in your credit score worthiness (I think 10%) is how long creditors have "trusted you" to have credit with them. You want that average to be 7 years or higher. So if you have 4 total credit cards that you've had open 20, 10, 5, and 1 years, the average age is 36/4= 9 years. If you cancel the 20 year card, it drops to   16/3=5.33 years. That would most likely drop your score 30 pts until the average age increases.