I did the same with a QS1 card to Venture. The closed account stays for 10 years. Just shows as closed by consumer on CR's and keeps the payment history and so on reporting. It doesnt go away till then.
A closed account in good standing can stay on your report for 10 years or more. I have an old JCP card, that I was AU on, which was closed January of 2004 still showing on my report. If you are asking about your online account, I don't have an answer...hopefully, someone will chime in!
Also when you sign in to your online account page it says in red account closed. Ref # ***********
What you need to do is call capital one and ask a csr or someone on a higher level (manager perhaps) to unlink the closed accounts from online banking. That is what I did with mine. You cant unlink closed cards online so you have to call them to do it. Other option is to unlink your active card from online banking and register again using a different sign on or username.
@Anonymous wrote:wanting to be tidy, and I guess a tad bit OCD, I have a couple of Cap1 accounts that have been combined and are closed.
For those that have done combinations, when do the closed accounts go away? I've tried chat and calling on the phone and haven't found a CSR yet that could be helpful yet. Any ideas or thoughts?
I can't put my finger on the thread(s), but I do recall reading where others were able to call and get transferred (?) to somebody who was able to remove the old account(s).
I don't remember if they had to re-register online or not, but I do know what you're asking about is possible. 
Sorry. I took it as your credit reports, not the online account. Now that I know what you meant. I can do the same thing. Want to rid the old QS1 showing up on my online account. Thanks experts.