Kusadasi to Izmir airport

Hi William,
I’ve done this route recently! The Havaş bus is super straightforward and reliable. It departs right from the main bus station in Kuşadası and goes directly to Adnan Menderes Havalimanı (Izmir Airport). The trip takes about 90 minutes depending on traffic. Tickets are around 550 TL right now, and you can just buy them right on the bus or at the little Havaş kiosk.
Depending on which map app you use or who you ask for directions, the departure terminal is listed online in a few different ways—you'll see it on maps as Kuşadası Otogar, Kuşadası Otobüs Terminali, or just Kuşadası otogar. Don't worry, they are all the exact same central terminal! The buses run pretty frequently throughout the day, usually every couple of hours. Just make sure to get there a little early to secure a seat, especially since August is peak season.
Just as a quick heads up though: we used Meet Transfer as 4 people and it actually came out to the same price as taking the Havaş bus. It might be worth looking into a private transfer if you are traveling with a group, since it picks you up right from your hotel and saves you the hassle of dragging luggage to the bus station!

https://community.ricksteves.com/travel-forum/turkey/bus-ride-to-izmir-airport-after-the-rs-tour-ends-in-kusadasi

RS wouldn't let you take the 'other' bus?

I am still not sure why the RS bus from the tour after ours will not take us! We will ask our guide. If you hear of anything positive let me know. Bill

I am still not sure why the RS bus from the tour after ours will not
take us! We will ask our guide.

William did you call the RS office and they specifically said no to your request? That's surprising. Your guide may or may not have any sway to change that decision though, but it's worth a shot to ask. I still think arranging a private driver will still be affordable and more certain, but that's my personal preference.

I wrote to RS and they are making it possible for us to take the RS tour bus on Saturday the 3rd. Our tour ends on Thursday the 1st. This group after us is staying in the same hotel so that makes this option easier. We hope the bus leaves early enough just kidding we have a noon flight. Bill

William that is good news, I'm glad they worked with you on that. Since they do change the departure time for each tour based on the flights for that group, make sure to connect with the guide directly so you don't miss the bus. Have a great time!

We are also ending the tour on October 3rd and are planning on taking the tour bus from Kusadasi to Izmir airport for our noon flight to Paris (via Istanbul). I’m not aware of the need to to prebook this bus ride back to Izmir. From the Itinerary received, it said this was an option , so hope it is!

It is available to you the day your tour ends. The difference is we are on the tour ahead of you and therefore have to make arrangements a head of time..