I made a mistake in my completed return, but I haven't mailed it yet. Can I reopen it and make the correction?

[DianeW · Accepted solution]

Yes.  Sign into your TurboTax account, then on the Tax Timeline select to "add a state return", you are not really adding a state return, but accessing your return.  Make the changes you need to make and then choose the file button again, selecting to mail your return.