So, we finally got around to filing N600 for my 12 y/o stepdaughter. Mom naturalized last November and we got her and her daughters US Passports the very next day so the N600 has not been a priority. Our rationale for paying the ridiculous N-600 filing fee is that passports do expire and constantly need renewed. While we got her passport easily, it was not trouble free since the agent at the Passport Agency said our evidence of actual physical custody was not adequate and he was quite insistent we provide additional school enrolment records. Since our next stop was dropping her off at school after her passport appointment anyways, it was incredibly simple to get what they asked for and email it in. But I could very much envision that that might be some sort of major crisis if a lost passport needed replaced overseas 30 years from now and she had the misfortune to get an ill-tempered consular agent. $1355 is ridiculous but we want the forever Certificate that never expires and is 'almost' unchallengeable.
Since it is a one-shot deal and the current political environment is.... mistake averse, I figured it was better to take our time, be cautious and make sure every detail was as correct as it could be.
We filed online. While I am a big proponent of online filing, it is worth noting that the online N600 has a number of major discrepancies and ambiguities so anyone going that route should very carefully compare the resulting pdf copy of the N600 with what they answered in the online form. Go through filling the entire online form, then before filing download the resulting pdf, AND the N600 instructions sheet, and go back through the whole entire thing, line by line, like about three or four more times until it all makes sense.
We used USCIS's own Policy Manual https://www.uscis.gov/policy-manual/volume-12-part-h-chapter-4 as almost a direct check list and guide book for the submission. We went straight down their list of evidence one by one in every category except for the notarized affidavits which we omitted. The USCIS policy Manual actually seems like the best N600 guide I found anywhere.
In any case we filed online March 14, 2025. Mysteriously she received two identical pdf receipt notices under the documents tab within an hour of filing. They are addressed to "mother c/o daughter" so maybe they are going to mail a copy to each(??). No immediate notice for reuse or scheduling of biometrics. Online our local USCIS Field Office (San Diego) lists 13 months processing time for N600 though I have seen some people report much faster results. No rush anyways because she has her passport already.
So now we wait.