Thomas Armstrong
Principal at Diameter Capital Partners LP
West Palm Beach, United States
Thomas Armstrong, Principal at Diameter Capital Partners LP is an active investor based in West Palm Beach, United States. This profile covers what Thomas Armstrong backs, at which stage, and how founders can reach out in 2026.
Thomas Armstrong is a Principal at Diameter Capital Partners LP, focusing on private capital.
Thomas Armstrong invests in Fintech and SaaS & Enterprise, typically at Early Stage Venture and Late Stage Venture.
- Investor type
- VC
- Stages
- Early Stage VentureLate Stage Venture
- Invests in
- FintechSaaS & Enterprise
- Location
- West Palm Beach, United States
- Typical check
- $3.8M
How to reach Thomas Armstrong
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About this profile
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Cite this page
Round Funded. "Thomas Armstrong." Round Funded investor database, updated November 3, 2026.
Stable URL, it will not change: https://www.roundfunded.com/en/investor/thomas-armstrong
Frequently Asked Questions
Who is Thomas Armstrong?
Thomas Armstrong, Principal at Diameter Capital Partners LP is an active investor based in West Palm Beach, United States. Thomas Armstrong invests in Fintech and SaaS & Enterprise, typically at Early Stage Venture and Late Stage Venture.
What does Thomas Armstrong invest in?
Thomas Armstrong invests in Fintech and SaaS & Enterprise, typically at Early Stage Venture and Late Stage Venture. Match your sector and stage, then reach out with a personalized pitch.
What stage does Thomas Armstrong invest at?
Thomas Armstrong typically invests at Early Stage Venture and Late Stage Venture. Lead with traction that fits the stage when you reach out.
What is Thomas Armstrong's typical check size?
Thomas Armstrong 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.