Recurring local guide · source checked
What the Fluff? Festival guide
A source-backed planning guide to Somerville's annual What the Fluff? Festival in Union Square, with the current edition and official updates.
Use the guide
What the festival celebrates
The festival honors the invention of Marshmallow Fluff and frames it as part of Somerville's tradition of local innovation. The official pages describe live music, Fluff-themed food, games, and public happenings in Union Square.
Start with the current edition
The official homepage lists the 2026 festival for September 19 from 1 to 5 p.m. It also says more 2026 information is coming. Maps, schedules, vendors, detours, and weather plans from prior editions should not be treated as the 2026 program.
Plan around Union Square
The official festival site describes Union Square as short on parking and encourages walking, biking, or public transportation. Recheck the current edition page before leaving because street access, bus detours, entrances, and bike services can change by year.
Why this page stays evergreen
This guide explains the recurring festival and points to each dated Camberville occurrence. The dated event page remains the place for a specific year's verified date, lifecycle status, source ledger, and corrections.
Current dated occurrence
Plan from the verified record.
Somerville · Union Square
What the Fluff? Festival 2026
What the Fluff? returns to Union Square on September 19, 2026, from 1 to 5 p.m.; the detailed 2026 program is still forthcoming.