350 Seattle is an environment-focused nonprofit that works toward climate justice by organizing people to resist fossil fuels, build momentum for healthy alternatives, and foster resilient, just, and welcoming communities. In filing year 2024, it reported an operating budget of $2.4M and total revenue of $2.9M; its largest listed funder was Sustainable Markets Foundation, which provided $2.4M in 2025, a level that alone does not indicate that the organization relies on a single funder for 50% or more of revenue.