Traditionally it's either or both sets of parents that throw the party in the first two months of the engagement. These days, it's pretty much accepted that anyone can host the party, including the couple themselves, some friends or other relatives.
i agree with the above note. there's no standard etiquette on who is invited and who plans these types of things these days (unless you have a cultural/religious criteria for it, that is). our engagement party had 140 guests and included an engagement ritual and the signing of an engagment document, so was quite involved. we planned it along with our parents and a team of friends.
we invited only people who lived in the same city as us, and chose to invite close family and friends, including folks we wouldn't be able to invite to the wedding itself. this seemed to work well, but guests really did see a "show" at ours. you may want to consider only inviting people who would be invited to the wedding itself.
Agree with everyone above. I recently came across something from an ettiquette site where it's the parents of the bride who would traditionally pay for the engagement party.
But nowadays, absolutely anything goes. There is no restrictions on who throws it, who attends or who hosts it. It can be as intimate or as extravagant as you want. My husband & I planned our engagement party with our parents and in the end, they surprised us by paying for it. We had 180 guests, but we also have large extended families so that was as small as we could get it without it turning into a wedding itself. For the fun of it, we opted to host it ourselves. We're not shy. We met in our senior year of highschool (different schools) & began dating 5 years later. So there was a bit of history & some funny stories to share. Good luck & Congratulations! PS - if you do host, get seperate microphones, much easier.
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