Boulder runs on an annual rhythm, and once you learn it you can plan a whole year around the same events that come back every spring, summer, and December. This is a boulder annual events month by month guide, built so you know what's actually still happening, because a surprising number of the events floating around on older lists have quietly died or moved. Every event below was checked against 2025 and 2026 sources. Where a date or a price hasn't been announced yet, I say so instead of guessing. Anytime you want to see what's on this exact week, our events calendar pulls daily from Boulder's venues.
Winter: January and February
January is about to change in a big way. Starting in 2027, the Sundance Film Festival makes Boulder its new home, running January 21 to 31 in its first edition here. Screenings spread across eleven venues, from the Boulder Theater and Chautauqua Auditorium to Macky Auditorium, the Dairy Arts Center, and eTown Hall, with premieres front-loaded into January 21 through 26. It's a genuinely different scale of event for a town this size, and our Sundance hub tracks the dates, venues, and logistics as they firm up.
One correction to the old January calendar: the New Year's Day polar plunge at Boulder Reservoir is gone. The American Cancer Society version skipped 2020 for reservoir construction and never came back on January 1, and the Boulder County AIDS Project plunge before it wound down years ago. The only plunge that survives now is the Special Olympics Colorado fundraiser, and it moved to early April, so don't anchor a New Year's trip on it. February used to hold the Boulder International Film Festival, but that has moved too (more on that below).
Spring: April and May
April is the month that stacks up fastest. Four or five things worth planning around all land within a few weeks of each other.
Film, ideas, and tulips
The Boulder International Film Festival is alive and well, it just re-dated. It deliberately moved to April so it wouldn't collide with Sundance, and the gamble paid off: the 2026 edition, its 22nd annual, ran April 9 to 12 with record attendance, 68 films from 29 countries, and 20 sold-out screenings. The 2027 festival is already set for April 8 to 11. If an old guide tells you BIFF happens in February or March, that guide is out of date.
The Conference on World Affairs brings a week of free panels to the CU campus, as it has since 1948. The 2026 run (the 78th) was April 13 to 16, with around 60 speakers across roughly 50 panels, all free and open to the public, and Malala Yousafzai as the closing speaker. It's one of the best deals in town: no ticket, just show up and listen to people argue about the world.
Downtown, the Tulip Fairy & Elf Festival sends the Tulip Fairy leading a parade of costumed kids around the Pearl Street Mall while roughly 15,000 tulips bloom along the bricks. In 2026 it fell on Sunday, April 26. It's short, it's free, and if you have small kids it's one of the sweeter mornings of the year.
Markets and the plunge
The Boulder County Farmers Market opens its Saturday season in early April and runs deep into fall. In 2026 that's Saturdays April 4 through November 21, 8am to 2pm, on 13th Street next to Central Park, with a Wednesday market added May 6 through October 7. It's the backbone of the local food calendar, and worth pairing with our restaurant guide if you're building a food-focused weekend.
The Boulder Polar Plunge is the plunge that's still real. About 400 people run into Boulder Reservoir for Special Olympics Colorado, with an after-party at Avery Brewing. In 2026 it happened Saturday, April 4. Recent years have raised roughly $80,000 for the cause, which is a lot of very cold, very willing volunteers.
Memorial Day weekend, the biggest of the year
Memorial Day weekend is Boulder's marquee weekend, and it's really two events at once. The Bolder Boulder is one of the largest 10Ks in the country, running since 1979 and finishing inside CU's Folsom Field with a Memorial Day tribute. The 2026 race drew 47,645 finishers on May 25. At the same time, the free Boulder Creek Festival takes over the creek path for its 37th year, pulling more than 150,000 people across three music stages and a 200-vendor market. Tucked inside it is the ticketed Creekside Beer Fest, a tasting with more than 20 Colorado breweries including Avery, Upslope, and Ratio. If you want the full brewery picture beyond festival weekend, our craft brewery guide covers the taprooms.
Summer: June through August
Summer is the long, easy stretch of the calendar, heavy on outdoor theater and music.
The Colorado Shakespeare Festival has been running since 1958 and fills the outdoor Mary Rippon Theatre from early June into early August. The 2026 season ran June 7 to August 2 with four productions, including Twelfth Night and a world premiere, on a stage that got a historic revamp for the year. Seeing Shakespeare outdoors under the Flatirons is one of those Boulder things that sounds touristy and then turns out to be genuinely great.
Tube to Work Day started in 2008 as a joke between two friends, Jeff Kagan and Andy Gruel, and somehow became an institution. Commuters in business attire float down Boulder Creek from the Eben G. Fine Park put-in, helmets and PFDs mandatory, ties optional but encouraged. The catch for planners: the date moves with the creek. It's landed anywhere from late June to late July depending on the year (2025 ran July 11, 2026 was listed for June 26), so treat it as "late June or July, set by creek conditions" and confirm close to the day.
Downtown keeps the summer full. Bands on the Bricks runs Wednesday evenings on the Mall (June 10 through July 29 in 2026), and the juried Pearl Street Arts Fest takes over the bricks in mid-July, July 17 to 19 in 2026. Up at Chautauqua, the Colorado Music Festival fills the auditorium from early July into early August.
Fall: September and October
Boulderthon is the town's marathon weekend, with the marathon and half finishing on Pearl Street. In 2026 it's set for September 27. October then slides into pumpkin farms, cooler mornings, and the wind-down of the farmers market season. The full autumn playbook, including where to find the pumpkins, lives in our fall guide.
Halloween belongs to the Munchkin Masquerade, when more than 100 Pearl Street businesses hand out candy to costumed kids age 12 and under. It's always October 31, 3 to 6pm. Downtown describes it as "not a parade but it feels like one," which is exactly right: it's a river of tiny superheroes moving down the Mall.
One caution for October planners. Downtown Boulder's Fall Fest ran October 3 to 5 in 2025 with an 80-plus maker market, free concerts, and a Fun Zone, but it's absent from the official 2026 Downtown Boulder events list as of this writing. Its status for 2026 is unconfirmed, so check boulderdowntown.com before you build a trip around it.
The holidays: November and December
December's centerpiece is the Lights of December Parade, when lit floats, fire engines, and a Santa finale roll through downtown. The route runs from 15th and Walnut up Broadway to Spruce. It ran December 13 in 2025 (parade slots filled with a waitlist) and is scheduled for December 12 in 2026, as the finale of Downtown Boulder's "Light Up the Holidays" season, which runs November 22 through December 12 in 2026.
The Boulder County Farmers Market also comes back one more time for a Winter Market at the fairgrounds in early December, so you can restock on local produce and gifts after the outdoor season closes.
Two more corrections for anyone working off an old list. The standalone Boulder Craft Beer Festival hasn't run since around 2020; Downtown Boulder's own page points people to Creekside Beer Fest as the successor. And Frozen Dead Guy Days left Nederland for Estes Park back in 2023, so it's no longer a Boulder-area event in the way older guides describe.
Frequently asked questions
Is the Boulder International Film Festival still happening?
Yes. BIFF is very much alive; it just moved from its old February or March slot to April so it wouldn't overlap with Sundance. The 2026 festival ran April 9 to 12 with record attendance, and the 2027 edition is set for April 8 to 11.
When is the New Year's Day polar plunge in Boulder?
There isn't one anymore. The January 1 plunge at Boulder Reservoir ended and never returned. The plunge that still happens is the Special Olympics Colorado Boulder Polar Plunge, which moved to early April (April 4 in 2026).
What is the biggest event in Boulder each year?
Memorial Day weekend is the biggest. It combines the Bolder Boulder, a 10K with 47,645 finishers in 2026 that ends inside Folsom Field, with the free Boulder Creek Festival, which draws more than 150,000 people to three music stages and a 200-vendor market.
When does the Boulder farmers market open?
The Boulder County Farmers Market opens its Saturday season in early April and runs into late November. In 2026 that's Saturdays April 4 through November 21, 8am to 2pm, on 13th Street next to Central Park, plus a Wednesday market from May 6 to October 7. There's also a December Winter Market at the fairgrounds.
When is Sundance coming to Boulder?
The Sundance Film Festival's first Boulder edition runs January 21 to 31, 2027, with screenings across eleven venues including the Boulder Theater, Chautauqua Auditorium, and Macky Auditorium. Premieres are concentrated in the first stretch, January 21 through 26.
Is Frozen Dead Guy Days still near Boulder?
Not really. Frozen Dead Guy Days left Nederland for Estes Park in 2023, so it's no longer the Boulder-area event that older guides list. If you see it described as a Nederland festival, that information is out of date.