The first two years of Massachusetts' millionaire tax has raised $3 billion more than expected. And rather than driving the rich away, IPS researchers found that the number of millionaires has increased.

They made the millionaire tax surcharge 3-4% and tied it to inflation. Public pushed it through on a ballot initiative. K-12 free breakfast and lunch. 90% HS grad rate. Free community college. Highest % of insured citizens. Free school vaccinations for every child, insured, citizen, or non-citizen.

Source: https://www.bloomberg.com/news/articles/2025-10-21/millionaire-tax-that-inspired-mamdani-fuels-5-7-billion-haul-in-massachusetts