After you file

If your status only says "printed" you did not file it.

“Ready to mail” or "Printed" means that your tax return has not been filed.  Either you could not e-file for some reason , or you chose to file by mail.  OR if you really did already mail your return, the software does not have any way to know that you put your return in an envelope and took it to a mailbox, so it will always say “ready to mail” in your online account.

TurboTax does not mail your return for you.  You have to print it, sign it, and mail it yourself.  When you mail a tax return, you need to sign it where it says "Sign Here" and write in the date you signed it by the word "Date".  Attach copies of your W-2 and any other documents that show taxes withheld to the left side of the papers where it says "Attach Forms..."

When you print your return, it will print with filing instructions that tell you where to mail it.  Pay careful attention to the address you mail your return to —federal and state returns do not get mailed to the same place.

It is not required, but is a good idea, to use a mailing service that will track your return or provide you with a receipt showing that the IRS got it--such as Fedex, UPS, or certified mail.  It will take about 4 weeks and then you can track the status of your return at the IRS website.

To finish a prior year return started in TT online:https://ttlc.intuit.com/questions/2559403-how-do-i-finish-a-prior-year-return-that-i-started-in-turb

To send your tax return by mail and get a receipt to see that the IRS and/or your state received it:

https://www.usps.com/taxes/welcome.htm

Or use UPS, Fedex, etc.

If you are getting a tax refund there is no penalty for filing your 2017 return late.  If you owed tax due, you need to pay it when you mail the return, and you can then expect a bill from the IRS for the additional penalty/interest you will owe.  TurboTax will not calculate that--the IRS will calculate it based on when they receive your payment and how much you owed.