Should I still use A number even if I am a naturalized citizen. If so which one?

[RKX1101 17]

I am a US petitioner and I am a naturalized citizen,

In form G325A and I129F they ask about my file number and alien registration number.

My question is, since now I am a US citizen, do I still use that number or leave it blank.

Some people here suggested to use the A number since it is also written on my naturalization certificate but my alien number is different than the one written on the certificate. I am confused as to which one I use if I use any at all.

Also is a file number (top of G325A) different than the Alien registration number or are they the same?

Thanks

[KayDeeCee 4,896]

Some people list their old A# and some don't. Either way seems to work.

List your naturalization certificate number where it asks though, for the questions about citizenship.