wording on plus ones

I think it should be the opposite... I would say don't put it on your website, but just invite the plus ones on the invitation.

For example, let's say your cousin Dave has been dating Sara for 3 years. On his invitation, instead of saying Dave and Guest, address your invitation to Dave and Sara.

Since many of the cousins are in high school, we will be addressing the invitations to their parents and family. EX: Mr. and Mrs. John Smith and Family.....

It sounds like an open ended plus 1 situation in the way you're wording it. as if the guests can decide to bring a friend or not. +1 is for an unamed & sometimes unknown guest or you're invited person.

if you want "Steve" to bring a date, name the date on the invitation envelope. or you can give him a +1, which indicates he can bring anyone he likes. if you dont want him to bring a date then address it to Steve only.

There still should be a polite way to word it.....

Monika, on the invitations the outside of the envelope says "Mr. & Mrs. John and Jane Smith and Family", the inside RSVP envelope will say "John, Jane, Amanda, and Peter", and these never include "plus ones". Agree that for those in relationships, even if they are not living together, you address the invitation to Mr. John Smith and Ms. Jane Jones, and RSVP envelope to John and Jane.

If you want to invite a minor with a guest, e.g., lets say you have a 16 year old cousin who you want to bring a guest, then you would send a separate invitation to Mr. Peter Jones, and inside the RSVP envelope is Mr. Peter Jones and Guest.

The best option may be - and this is a pain - for those whom your worried will assume a Plus One, to pre-fill the "M_________" line for them with the specific names of who's invited. This would make it clear they are only to respond for the people listed. I'm not aware of any reason not to do this, and I believe it's not automatically done primarily because of the time and effort it would take to add another manual task to the process.

Or on your website create a section under the Reception part that says "If you're unsure about anything in your invitation or response card, please contact us - we don't want anyone to be confused!" And then put on the website a sample envelope and response card, with something like "Please don't forget to write your names when you respond!" So it's not directly obvious the point is to educate them how to respond.

In fact, this is something I read as a tip, that some people DO forget to put their names, and just mark the "accept"/"decline", so you get it, but don't know who sent it... the recommendation was to put a light pencil number on the back that you can match up to your invite list, in case someone forgets... so putting a reminder to put their names in on your website would not be inappropriate I think. But you would either write the names for them OR put the sample and message on your website. Doing both is overkill.

That's the best I can think of!

There isn't. if you want them to bring someone, you list them. typically if they are in a relationship you know the name and write it. if they arent in a relationship, they either get a +1 and you can't say it has to be a relationship person, it would be anyone they want. or you just don't give them a plus 1.

your website can say adults only type stuff, but who can come is not for the website. if you give +1, and its not a specific person by name, they can bring anyone, you dont get to pick.

When talking about minor cousins still living with Aunt/Uncle, address the envelope as "...and Family" and on the RSVP card write out everyone's names including those significant others that you know of (I would ask someone beforehand to make sure you're not forgetting anyone)- a little more work for you, but it eliminates any confusion for your family.

For adults just address the envelope with both names - even if they don't live together, send the invite to the person in the couple you are closer to and just write both names.

Honestly, think back to when you were in high school. You probably thought that your boyfriend (whether you were together 2 days or 2 years) was a serious relationship. I think your best bet would be if you know the person is in a serious relationship you can write the other person on the inner envelop. I decided to not include a "guest" and noted on my wedding website that if you feel that you want to bring a guest you can contact FH or myself to discuss the situation. I feel like if the person is important enough for the invited guest to reach out in order to bring a guest then that relationship is serious.

Nope. You can't. You either invite people with a random guest or you don't. Everyone thinks their relationship is serious.

Im only having a guest if they are in a serious relationship or wont know much of anyone. thats it.

If they are in a serious relationship, you should take the time to learn the name of their significant other and put their name on the invitation (Facebook creep if you have to). As Celia said, everyone thinks their relationship is serious.