If you live within a ten-minute walk of the plaza, you already know Union Square runs on two different calendars in early fall. The old one belongs to Somerville Avenue: farmers market Saturdays, the Fluff Festival in September, Bow Market spilling out onto the sidewalk. The new one belongs to Prospect Street, where the Green Line station and the first phase of the USQ redevelopment have quietly become their own gravitational center.
For the next two months, both calendars are running at once. That has not really been true before, and it will not be true in quite the same way once the next round of USQ tenants open. This is a good stretch to pay attention to.
The Saturday plaza is still the plaza
The Union Square Farmers Market is in its 22nd year, running Saturdays 9am to 1pm through October 31 on Union Square Plaza with sixty-plus producers. Somerville Times readers voted it Best Farmers Market in Somerville in 2025, which sounds like small talk until you stand at the corner of Somerville Ave and Union Square at 10am on a late-August Saturday and try to move.
Two dates to keep straight this season. There is no market on September 19. That Saturday, the plaza is closed for Fluff Fest. Every other Saturday through Halloween weekend, the market runs rain or shine.
The rest of the plaza calendar is not a random pileup. It is a sequence, and if you live here, walking it in order is the difference between a fall that feels like a lot of separate flyers and one that feels like a season.
| Weekend | On the plaza / Somerville Ave | Practical note |
|---|---|---|
| Every Saturday through 10/31 | 22nd Union Square Farmers Market, 9am–1pm | Skip 9/19 |
| Saturday, September 19 | 21st What the Fluff? Festival, 1–5pm | Somerville Ave closed School St to Warren Ave, 11am–8pm |
| Sunday, September 20 | Fluff Fest severe-weather date | Only used if 9/19 is called |
| Ongoing | Bow Market programming, Thursday–Sunday | See the Bow calendar for specifics |
The Fluff calendar, decoded
The 21st annual "What the Fluff? A Tribute to Union Square Invention" lands on Saturday, September 19, 1pm to 5pm, with the severe-weather date the next day. This year's theme is "Legally Fluff: A Toast to Union Square," which the festival is running as a nod to Somerville Ave's long list of local drinks producers. The festival is co-produced by Union Square Main Streets and the Somerville Arts Council, and it honors Archibald Query, who invented Marshmallow Fluff in Union Square in 1917.
The event has grown well past a novelty at this point. Last year's 20th anniversary drew thousands, and Mayor Katjana Ballantyne used the anniversary press release to note that Union Square had recently been named the 38th coolest neighborhood in the world. Read that ranking however you want. What matters if you live here is that the crowds now behave like a real festival crowd. Bike valet is free at both entries, and driving into the square between 11am and 8pm on that Saturday is not a plan. Somerville Ave from School Street to Warren Ave closes to traffic for the day.
If you are trying to combine the market with the festival, you cannot, at least not on the same block. The market takes September 19 off. The plaza belongs to Fluff.
Bow Market has its own weather
A block off the plaza, Bow Market at 1 Bow Market Way keeps a schedule that never really matches the festival calendar and that is part of its charm. This is where the neighborhood's small-business overflow lives now, and the fall programming leans harder into it than the summer version did.
Three things to know for the next two months. The Curated Vintage Market, run by Blue Bandana Relics and Biscbro & Co., brings eighty-plus vintage vendors across Bow, Somerville Ave, and Union Tavern for a full-day takeover on its scheduled Sundays. The Somerville Art Fair's Art Salon meets upstairs at Bow on rotating evenings, low-pressure and free to wander. And Side Quest Books & Games and Remnant Brewing run Bow Market's Renaissance Faire day, which closes with an Enchanted Forest Ball in the upstairs event space and, more usefully, Remnant's Oktoberfest lager and Hella Crispy corn lager on tap. Rebel Rebel pours mulled wine when the weather turns. Viet Citron cooks a grilled chicken quarter they call the Feast of the Fowl, which is not a phrase you use when it is 85 degrees.
The point is that Bow's fall calendar is where the neighborhood's rhythm lives between the marquee dates. If you already live here, the correct move is to check Bow's own calendar the week of, rather than deciding in advance.
What is actually new to eat
Two openings from earlier in 2026 are worth walking to if you have not yet. Both are within Union Square proper and both were covered by Boston Restaurant Talk and Patch when they opened.
Kush by Saba took the space at 5 Sanborn Court that had been Wade BBQ and, before that, Littleburg. Chef Saba Wahid Duffy, who won Chopped: Martha's Rules in 2021 and ran the concept as a food truck before this, opened the brick-and-mortar on April 28. The menu is modern Mediterranean with global drift. If the name sounds familiar to Fluff Fest regulars, Duffy emceed the Fluff 'N Jam Stage at last year's 20th anniversary festival, which is the kind of local overlap that tells you which openings will stick.
Hen took over the former Red House at 24 Union Square and now serves khao man gai, the Thai chicken-and-rice street dish, with the usual choices of boiled, crispy, or spicy chicken. It is a lunch move more than a dinner one, and it fills a gap that has been open on that block since Red House closed.
The Prospect Street pivot
Now the second calendar. On July 14, 2026, Connect CRE reported that Workbar will open a roughly 10,000 square foot coworking location at 50 Prospect Street in the Prospect Union Square residential tower, adjacent to the Union Square Green Line station. Late fall 2026 opening. Workbar previously operated a Union Square location that opened in 2015 and closed some years back, so this is a return rather than a first entry. The lease also makes Workbar the second commercial tenant in the broader USQ project.
Zoom out and this is the piece of Union Square that has been changing fastest. The USQ redevelopment, run by US2 with Magellan Development, is a 20-acre transit-oriented plan around the Green Line station that is planned to include more than 2.3 million square feet of lab and office space, about 1,000 housing units, retail, a hotel, and new public gathering spaces. US2 President Greg Karczewski told the Somerville Redevelopment Authority in March 2026 that four years into the Green Line station's operation, its impact on the neighborhood has been significant, which is putting it mildly.
"Union Square has long been a place where small businesses, entrepreneurs, artists, researchers, and neighbors come together. As the district continues to grow around transit, new housing, public space, and commercial activity, flexible workspaces can help support the people and ideas that keep Somerville's local economy moving forward."
That is Workbar's Sarah Travers explaining why they came back. Translate it out of press-release English and it says something simple: the Prospect Street side of Union Square now has enough weekday foot traffic to justify a 10,000 square foot coworking bet. Five years ago it did not.
A practical map for the next eight weeks
If you already live in Union Square or the streets that feed it, here is the compressed version:
- Saturday mornings through October 31, walk to the plaza before 11am for the farmers market. The best produce moves before the last hour.
- Saturday, September 19, plan around Fluff Fest. Bike or walk. Route 87 buses are historically detoured 11am to 8pm on Fluff day, so check MBTA alerts that week.
- Between marquee weekends, check Bow Market's calendar on Thursday for the coming Sunday. The vintage-market Sundays and the Ren Faire day are the ones worth blocking out.
- Kush by Saba for dinner, Hen for lunch, Remnant for after. That is a full Union Square day without repeating a block.
- Watch Prospect Street. When Workbar opens in late fall, that side of the square starts pulling weekday coffee traffic away from the Somerville Ave side, and the corner cafes will feel it.
What this actually means if you live here
Every neighborhood has a moment when a long-planned redevelopment stops being a rendering and starts being a place people walk to on a Wednesday. Union Square is in that moment right now. The plaza calendar still runs the weekends, and probably will for years. The weekday calendar has already migrated a block south to Prospect Street, and this fall is the first stretch where that split is visible to anyone paying attention.
For homeowners already on Bonair, Stone, Sanborn, or Prospect Hill, that split is worth watching, because it tends to reshape which corners feel busy at which hours. That is not a market call. It is a walking observation, and the next two months are the ones to make it.
If you have questions about how the Union Square block you live on is changing, or you want to talk through what any of this means for a home you already own here, the Lauren Holleran Team lives and works in these blocks. Talk to our Cambridge & Somerville experts.
