The Declaration of no Impediment to Marriage is a document that you have to sign before your marriage ceremony. It will be on the reverse side of the Official Certificate of Marriage that you will sign on your wedding day. It is usually signed at the rehearsal, or the last time that you meet with the celebrant before the big day. It must be signed before you are married. It can be signed on the day if needs be, but it has to be signed legally before the ceremony takes place.
This document is basically a Statutory Declaration that you are over the age of 18 and there is no legal reason that you cannot be married to the person that you are about to marry. (If you are under 18 years of age you can still sign the paperwork, but you have to get a court approval to be married and it must be to someone that is over the age of 18) It states that you are a person who has never been validly married, or that you are a divorced person, or a widow or widower, and that there is no reason you cannot be married to the person that you are marrying.
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