Marrying a US citizen after filing N-400

You need to bring absolutely nothing. All you need to do is verbally update your marital status prior to being placed under oath, and if it'll make you feel better (like when in the confession booth) bring along your marriage certificate and a copy thereof.'

During the interview, the officer will review your N-400 application to confirm that your answers are accurate and up to date. He/she will update the application to reflect your changed marital status. I would suggest bringing your marriage certificate and a copy, just in case. Best of luck.

Bring your marriage certificate, and inform the officer you got married.

A verbal marital status update with a marriage certificate copy at the interview should suffice.

Bring a copy of your marriage cert and make verbal attestation re same during interview.

Although you do not need to bring anything to the naturalization, it would not hurt to bring along a copy of the marriage certificate and make sure that you verbally update the application as to marital status during your interview.