marital status

[wika]

Hi!
Me and my significant other are applying to the citizenship. We have been living under common low for almost 20 years. We came to USA in 2009, and since then we have been living together, filing taxes together as married, bought a house together and have one child. Since we are not legally married , we are hesitating about putting married on the N-400 form. I don't think they are going to request any marriage certificate since we are applying separately after being 5 years as green card holders, but he wants to put single. We can't not apply until we get an agreement on that, which we don't have yet.
What would be your advice?
Thanks!

 

[Jackolantern]

If on the N-400 you state that you are married, and you have not already provided them with a marriage certificate during an earlier immigration process such as your green card application, they probably will ask for the marriage certificate at the interview, even though you're not applying for citizenship based on marriage and didn't obtain your green card through marriage. Your marital status will be displayed on the naturalization certificate, and marital status can have other immigration significance such as affecting whether your existing or future children can obtain US citizenship through you.

What marital status did you put on the green card application? Single? If you put single back then and now you want to say you're married, when will you say is your marriage start date (which is requested on the N-400)? What evidence will you show to prove that you became married as of that date?