Having an anniversary party for yourself is a way to celebrate the love that you've shared. Throwing an anniversary party for someone else allows you to help show them how much they are loved as a couple. Either way, when you are planning an anniversary party, it is important to understand when to send out the part invitations so that you can make sure everyone who would like to come is able to do so.
If you are throwing yourself an anniversary party, the amount of time you'll want to leave between sending out the invitations and have the party will differ depending on the party. For a casual evening or afternoon get together, send out invitations two to three weeks ahead of time. This will give everyone you have invited a chance to RSVP so that you can have a guest list for your party.
When throwing an anniversary party for someone else, you'll need to leave a bit more time to send out invitations. This is because these are usually bigger and more complex affairs and you are going to want to make sure that everyone would like to come is able to do so. For these types of get together events, you will want to send out invitations at least a month in advance. If the party you are planning is very large, think about sending out invitations even sooner. As always, include directions and a date for RSVPs to be sent.
When you are setting up an anniversary party that is a surprise for the couple, it takes more time to prepare. For these events, you'll want to at least send out information about 5 or 6 weeks in advance, so that people can make plans to attend the party. Be sure that you specify that the party is a surprise party, so that no one spills the beans to the couple.