Those attending a vow renewal ceremony may want to consider a donation to the couple's favorite charity in lieu of a gift, since a gift is not required. The couple and attendees should keep in mind that a vow renewal ceremony is different than a wedding ceremony, which means rules and etiquette are different as well.
A vow renewal ceremony is seen as an intimate gathering of the couple's friends and family. It is also referred to as a reaffirmation ceremony and can be done at any time. For example, a couple who eloped to the Bahamas may want to have a vow renewal ceremony for those who were not at their wedding. Sometimes couples celebrating a marriage milestone such as 15 or 20 years choose to do a vow renewal ceremony just as a reminder of the words they spoke years ago.
Etiquette for this type of ceremony is fairly loose and somewhat casual. Venue, for example, can be anywhere from a grand church to a quaint backyard. Guests are usually friends and family, and quite often couples favor the reception to be something like a backyard barbecue or dinner at a local restaurant. One piece of etiquette that is followed, however is not registering for gifts. Because it is a simple vow renewal ceremony, couples should consider the attendance of their guests as gift enough.