Startup profile for Substack: what they do, why they are interesting, stage (growth), industries, and links to our funding articles. Part of the Venture Capital Tracker startup directory.

Startup profile · funding coverage

Substack

Publishing platform for independent writers with subscriptions and network effects.

Stage

growth

Status

private

Coverage

full

Why Substack is interesting

Substack remains the reference independent media business model. a16z’s continued involvement keeps it on the “on fire” media-tech map as AI changes content economics.

Key facts

  • Series B (Mar 2021): $65M at ~$650M led by a16z (Andrew Chen); YC Continuity prior participant (Reuters)
  • Series A (Jul 2019): $15.3M led by a16z (public reporting)
  • Co-investors not in VCT directory: Y Combinator Continuity
  • Source: https://on.substack.com/p/investing-in-writers
  • VCT directory co-investors: none mapped (non-directory syndicates noted above); reviewed 2026-07-24

Investors in our directory

Funds linked from Substack's profile — open a fund page for stage focus and related deal articles.

Industries

Media & Entertainment Consumer

Industry hub pages are rolling out from our fund-derived baseline taxonomy.

FAQs about Substack

Funding context and why this company shows up in venture coverage.

Substack is listed among Andreessen Horowitz (a16z) investments; no additional VCT-directory co-investors were identified in public sources reviewed 2026-07-24.
We track a16z-backed companies that are strategically relevant for founders and investors following AI, American Dynamism, crypto, bio, and enterprise software.

Last updated: 2026-07-24