Something big is headed for downtown Boise this summer, and if you love live music, cosplay, immersive experiences, pop culture, panels, performances, and wandering through rows of creative vendors with a drink in hand, this one deserves a spot on your calendar.
Cosma Con: Day Zero is happening Saturday, July 25, 2026, and it’s not your typical convention or your typical music festival. It’s a one day hybrid built to bring both worlds together across downtown Boise, with programming spread across Boise Centre, Idaho Central Arena, and Grove Plaza. The event runs from 10 AM to 10 PM and brings together celebrity panels, community panels, concerts, cosplay, gaming, food, drinks, vendors, and interactive fan experiences all in one place.
What makes Cosma Con feel especially fun is that it is not trying to fit into one lane! One minute you could be catching a celebrity panel, the next you are shopping artist booths, then heading toward a mainstage performance, and somehow still finding time for cosplay champions, workshops, and local eats. That mix is exactly what makes this event feel fresh for Boise.
So what exactly is Day Zero?
Day Zero is Cosma Con’s single day summer event, but calling it “just” a one day event does not really do it justice. Downtown Boise is basically turning into a full scale playground for fans, creators, artists, music lovers, and anyone who likes their events with a little more personality. Official event listings describe it as a one day convention and music festival hybrid with free interactive fan experiences, plus celebrity and community panels, curated vendors and exhibitors, and live performances from local and national acts.
There are also more than 100 vendors and exhibitions expected, which means this is the kind of event where you will want comfortable shoes, a game plan, and probably a second lap because one walk through is never enough. Between the shopping, the guest appearances, the free gaming and workshops, and the energy of downtown in the middle of summer, this has all the ingredients for one of those “you had to be there” Boise weekends!
The guest lineup already has people talking
Cosma Con is coming in strong with a lineup that spans film, fandom, cosplay, and music. Current event listings and promo pages name Dan Fogler, Christopher Mintz Plasse, Emma Caulfield, and world renowned cosplayer Yaya Han among the featured guests. On the music side, Almost Monday and Meet Me At The Alter have also been announced as headliners.
That kind of lineup gives the event a little extra spark because it is not built around just one type of audience. It is designed for the people who want to see a panel, catch a live set, shop something cool, and still have time to take in the costumes, performances, and surprises along the way.
The local roots make it even better
One of the coolest parts of Cosma Con is that it did not come out of nowhere. It was started by Boise local Michelle Allred, with roots in her love for art, tech, music, cosplay, and immersive experiences. That local foundation matters because you can feel when an event is built by people who actually want to create something for their city, not just drop in and leave.
That local spirit also shows up in how Cosma Con is being positioned. Event partners describe it as made by locals for locals, which feels especially fitting for Boise right now. The city keeps growing, and so does the appetite for events that feel creative, ambitious, and a little outside the usual formula.
Final thoughts
If you have been waiting for a Boise event that feels bigger, more imaginative, and way more interactive than the usual weekend plan, Cosma Con: Day Zero might be it.
Passes are already on sale for Day Zero, so now is a very good time to grab yours before everyone else starts circling this one on the calendar!
XOXO,
The Boise Socialite
Hi, I’m Cait. I love sharing hidden gems, local eats, and fun things to do around Boise. From cocktails and brunch to events and weekend adventures, Boise Socialite is your guide to discovering what makes this city so special.
