Substack

โ— Verified today Last updated: Mar 23, 2026 Data verified: Apr 24, 2026

Substack: $650M valuation, IPO Readiness 32, Series B. Newsletter publishing platform enabling writers to build paid subscription audiences. Track live on The IPO Stack.

Series BMedia Technologypre-ipo
32
/100
IPO Readiness Score
Grade F โ€” Early Stage
TechStackIPO proprietary score based on funding scale, valuation, stage progression & momentum.
Track Substack โ†’

Newsletter publishing platform enabling writers to build paid subscription audiences.

Valuation
$650M
Total Funding
$82.3M
Stage
Series B
Sector
Media Technology
Headquarters
San Francisco, CA
CEO
Chris Best
IPO Status
pre-ipo

Funding History

Round Amount Date Lead Investors
Series B $65M Mar 2021 Andreessen Horowitz
Series A $15.3M Jul 2019 Andreessen Horowitz
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Track Substack IPO timeline, funding rounds, investor activity, and valuation on TechStackIPO โ€” the pre-IPO intelligence platform.

Frequently Asked Questions

When is Substack going public? +

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.

What is Substack's current valuation? +

Substack is valued at $650M as of March 2021. This valuation is based on its most recent private funding round tracked by TechStackIPO.

How can I invest in Substack before IPO? +

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.

What is Substack's IPO Readiness Score? +

Substack scores 32/100 (Grade: F) 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.

How much total funding has Substack raised? +

Substack has raised $82.3M in total venture capital and private equity funding, with backing from Andreessen Horowitz.

Who are Substack's key investors? +

Substack's notable investors include Andreessen Horowitz. Full investor details, funding round history, and lead investor breakdowns are available on TechStackIPO.

What sector is Substack in? +

Substack is a Media Technology company. Newsletter publishing platform enabling writers to build paid subscription audiences.

Institutional Research
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