Overview The Big One is Do512's free, all-day SXSW party in Austin: one band an hour, from mid-afternoon to midnight. In 2026 it filled Radio/East on March 14 with nine acts, from Sex Mask at 3 p.m. to Sun Room at 11, and entry was a free RSVP on Do512. Do512 is Austin's events guide and bills itself as the unofficial guide to SXSW week; its 2026 materials count 17 years of free SXSW parties, with The Big One alongside The Smoke Show and the Do512 Lounge Sessions. On site Doors opened at 2 p.m. in 2026 and the bill ran straight through: Sex Mask, Men An Tol, The Braymores from Barrington, Illinois, The Dirty Turkeys, Couch Dog from Los Angeles, Sun Atlas, Radium Dolls, Tropa Magica and Sun Room. An RSVP does not guarantee a spot; entry is first come, first served. Do512 made a Spotify playlist of the lineup, and one of the 2026 sponsors ran a sweepstakes for an RV getaway from the party page. Talent and Influencers The 2017 edition at Barracuda ran Broncho, WAND, Tkay Maidza, White Reaper, NE-HI, Dream Wife, Ian Sweet, Post Animal and Austin's Sweet Spirit, and in 2026 Tropa Magica and Sun Room closed the night. Track record Do512 billed The Big One in 2017 as its final party of SXSW, and in 2026 as its annual Big One and the biggest party of its year. The 2026 edition ran 10 hours, from 2 p.m. doors to midnight. Brand presence The 2026 party thanked three sponsors by name on its event page: Outdoorsy, which ran the RV getaway sweepstakes, Wild Blood Premium Coconut Water and T.H.C Dispensary. Do512 sells its SXSW parties with one presenting partner, billed as "[Brand] Presents" on every poster and post, and supporting partners below it. The presenting package in Do512's 2026 offer adds a branded media run on Do512.com and its daily Top Picks email, an activation space and main-stage signage, product at the bar, VIP tickets, and a post-event photo and video recap.