When to file N-400...

[shinkansen]

When can you file N-400 (If married to USA and have a GC)... 3yrs from marriage date?

Is there a residency requirement?... ie., can't be outside of the US for X amount of time?

I couldn't find exact answers to those on the USCIS forms... Which doesn't surprise me. Thanks for advice.

 

[Flydog]

Download the Guide to Naturalization. All the requirements are explained there.

If you have have had a green card AND been married to a US Citizen (both conditions) for 3 years, or if you have had a green card for 5 years, then you meet one of the rules (in fact, you can apply 90 days earlier than that 3 or 5 year anniversary).

Yes, there is a residency requirement. There is also a "presence" requirement.

In each case, the Guide lists the definitive rules - much more clearly than a posting here will.

Your first steps should be to download and read the Guide, and then to re-read the instructions. That was all I need to figure out how to fill in the form. If you need more info, this forum is a great place to ask questions.