Typical seed round size for biotech startups in Boston
Based on 39 Form D filings by Boston biotech issuers at seed stage, filed Nov 2024 – Oct 2026. Updated monthly. Change any segment to compare.
The numbers
- Median seed raise: $4.2M
- Middle half of rounds: $1.9M – $6.3M
- Filings in sample: 39
- Rounds under $1M: 10%
- Rounds over $5M: 31%
- Updated Oct 2026
Read this number carefully
Form D undercounts small SAFE rounds and rounds that rely on other exemptions. Treat the median as a ceiling for "typical", not a target.
Compare segments
Biotech · Seed · Bay Area ($3.9M)
Biotech · Seed · San Diego ($1.9M)