Should I amend my returns?

[Mgygdl]

I'll try to be as clear as possible with my question and explaining the scenario. 

For the last 4 years, I checked the single box for my W-4s but claimed 3 dependants. I filed taxes all of those years. 

 When prompted by the turbo tax program for marital status I checked single and claimed my 3 children. Turbo tax suggested to file as Head of Household since I was indeed living with my children and providing for them. So those years I filed as HH but still checked the single box.

My ex and I haven't seen each other in 5 years but we are still legally married. 

Hence my question, did I file my taxes incorrectly all of those years by checking the single box instead of MFS regardless of still filing as HH? Am I  supposed to amend? 

This year I checked the box MFS and still HH. Am I going to be penalized in any way?

[ThomasM125]

You are allowed to file as head of household even if married, provided you lived apart from your spouse for at least the last half of the year. So if you filed as head of household, you filed correctly.

You should answer in Turbotax that you are married, but when you file as head of household, that wouldn't show up on the tax return. It would just show that you were head of household.

[Mgygdl]

Thank you so much for clearing that up for me.  I was afraid I had filed incorrectly all of those years for claiming single instead of MFS. 

I'm going  to go ahead and file my taxes since I don't have to amend anything.