Bill Castellano, Partner at Pareto Private Equity is an active investor based in Oak Brook, Illinois. This profile covers what Bill Castellano backs, at which stage, and how founders can reach out in 2026.
William Castellano is a seasoned executive, board director, and entrepreneur who has founded and grown successful ventures in technology and financial services.
Bill Castellano invests in SaaS & Enterprise, Fintech and Manufacturing & Industrial, typically at Early Stage Venture and Late Stage Venture.
- Investor type
- VCPE
- Stages
- Early Stage VentureLate Stage Venture
- Invests in
- SaaS & EnterpriseFintechManufacturing & Industrial
- Location
- Oak Brook, Illinois
- Typical check
- $3.8M
How to reach Bill Castellano
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About this profile
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Round Funded. "Bill Castellano." Round Funded investor database, updated November 3, 2026.
Stable URL, it will not change: https://www.roundfunded.com/en/investor/bill-castellano
Frequently Asked Questions
Who is Bill Castellano?
Bill Castellano, Partner at Pareto Private Equity is an active investor based in Oak Brook, Illinois. Bill Castellano invests in SaaS & Enterprise, Fintech and Manufacturing & Industrial, typically at Early Stage Venture and Late Stage Venture.
What does Bill Castellano invest in?
Bill Castellano invests in SaaS & Enterprise, Fintech and Manufacturing & Industrial, typically at Early Stage Venture and Late Stage Venture. Match your sector and stage, then reach out with a personalized pitch.
What stage does Bill Castellano invest at?
Bill Castellano typically invests at Early Stage Venture and Late Stage Venture. Lead with traction that fits the stage when you reach out.
What is Bill Castellano's typical check size?
Bill Castellano typically writes checks around $3.8M. Use it as a signal for whether your raise fits their stage.
How do founders reach investors like this?
Round Funded lists active investors with verified, professional contact details for signed-up founders. Filter by sector, stage and location, then send a personalized pitch from your own inbox.
What is Round Funded?
Round Funded is an investor database and outreach platform for startup founders. It lists 60,000+ active investors with verified contacts, filtered to recent investment activity, and lets founders send personalized pitches from their own Gmail, track replies, and share a free Data Room. Round+ starts at $99 per month with a 3-day trial.