Save the dates should be sent out in April/May invites at the End of June beginning of July. Unless you are having the wedding on labour day weekend than send your invites out at the end of May beginning of June
I am probably going to send both my save the dates and invitations early. My reasons are I have family who live in BC and Ontario who will need to save for flights and accommodations. I had called my one aunt and she wasn’t even aware I was getting married. I also will be sending out invites earlier so that if I have people who can’t make it then I can invite others. I kind of wish weddings weren’t so expensive and that I would love to invite everyone.
We didn’t send out save the dates and a lot of my family from out of town were starting to ask for details as they need to plan so we decided to send them this month for our aug wedding. My fiancé’s aunt got hers and made a comment about how she’s never gotten a wedding invitation so early. I don’t get why some people feel they have to wait until 2 months or so to send them out!
May is a good amount of time I think, considering you have let people know the date already.
I wanted RSVP's back 2 months before to have that time to work on chasing people who didn't RSVP and the seating chart. We are sending ours out in April for a July wedding, so we are only giving people 1 month to RSVP. But, we did send out save the dates, so out of towners have already started booking flights and accommodations!
May for a September wedding sounds good to me. We wanted to send ours in March or April (we're getting married on August 4), but we'll have to wait until late May to be able to include our menu options, since guests have to choose in advance. Because of that, we'll need to make sure all of the out-of-towners know the date sooner. They do constitute most of our list - including us - and the town is a popular summer destination.
We are getting Married on August 25. We have collected about half of the addresses needed. We are aiming to send them out in March. Because our wedding is in the summer, we thought the earlier the better. For a September wedding I'd say beginning of April would be good. You'll need to provide your caterer with final numbers usually about a month ahead.