Substack: $650M valuation, IPO Readiness 58, Series B. Newsletter publishing platform enabling writers to build paid subscription audiences. Track live on The IPO Stack.
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Track Substack IPO timeline, funding rounds, investor activity, and valuation on TechStackIPO — the pre-IPO intelligence platform.
Substack has not announced a specific IPO date as of 2026. Track TechStackIPO for the latest funding milestones and IPO signals. Subscribe to The IPO Stack newsletter for weekly updates.
Substack is valued at $650M as of March 2021. This valuation is based on its most recent private funding round tracked by TechStackIPO.
Accredited investors can access Substack shares through secondary market platforms, pre-IPO investment funds, and broker-dealer platforms that facilitate private company transactions. TechStackIPO's marketplace tracks available access options. Note: pre-IPO investments carry higher risk and limited liquidity compared to public market investing.
Substack scores 58/100 (Grade: C) on TechStackIPO's IPO Readiness Index. The score evaluates funding scale, valuation trajectory, funding momentum, stage progression, and company maturity. Scores above 70 indicate strong near-term IPO potential.
Substack has raised $90M in total venture capital and private equity funding, with backing from Andreessen Horowitz.
Substack's notable investors include Andreessen Horowitz. Full investor details, funding round history, and lead investor breakdowns are available on TechStackIPO.
Substack is a Media Technology company. Newsletter publishing platform enabling writers to build paid subscription audiences.