Substack is a private subscription publishing platform for newsletters and paid posts. It helps writers publish, manage subscriptions, and keep most of the revenue, which can appeal to accredited investors seeking private tech exposure.
Access to pre-IPO shares is available to accredited investors through UpMarket.
Latest Price
$1.1B
Series C, Jul 2025, Perplexity
UpMarket Estimate
$1.1B
Based on UpMarket valuation model
How to Invest in Substack Through UpMarket
Substack shares are not on public exchanges. UpMarket provides accredited investors access through secondary market transactions.
Step 01
Verify accredited investor status
Confirm eligibility under SEC Rule 501 of Regulation D. Income or net worth threshold applies.
Step 02
Create an UpMarket account
Complete KYC/AML onboarding. Typically 1–2 business days. Licensed rep assigned on signup.
Step 03
Review available Substack offerings
Full offering memoranda and risk disclosures provided before any commitment is required.
Step 04
Complete subscription documents
Review and sign subscription agreement. All documents handled digitally through the platform.
Step 05
Fund your investment
Wire transfer or ACH. $50K minimum. Funds held in custodial account until close.
Pre-IPO investments are illiquid, speculative, and involve risk of total loss of capital.
$1.3B+
UpMarket has brokered over $1.3 billion in alternative investments*
*Includes principal invested and appreciation of investments originated via the UpMarket platform based on historical trade volume and valuation estimates through March 31, 2026. Of the total, approximately $301 million is managed by UpMarket Management, with the remaining originated investments managed by affiliates. Past performance is not predictive of future results.
Valuation Growth Over Time
Post-money valuation by round
Previous roundsMost recent
Date
Round
PPS (split-adj.)
Valuation
Jul 2025
Series C
$1.1B
Why Investors Are Watching Substack
Growth Signal
Substack reported $29M revenue in 2023, up 50% YoY
Sacra says Substack generated $29M revenue in 2023, reflecting 50% year-over-year growth. The same analysis pegs the company at a $1.10B valuation in 2025, implying continued investor confidence in scaling.
Competitive Moat
Substack’s subscription model retains writer audience ownership
Contrary Research says Substack positions itself as an “economic engine for culture,” letting writers grow and retain their own audience. The company’s subscription-first model avoids ad dependence and has supported platform growth.
Market Opportunity
Substack reached 3M subscribers and 20M active users
Contrary Research reports Substack has 3 million subscribers and 20 million active users. That scale leaves room to expand from newsletters into a broader platform for paid cultural production across podcasts and video.
Interested in Substack stock? Fill out the form above or sign up directly. Subject to availability. Accredited investors only.
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No. As of March 2026, Substack is a private company and does not trade on any public stock exchange. Accredited investors can access Substack shares through UpMarket, a FINRA-registered broker-dealer that specializes in pre-IPO investments.
Substack does not have a public stock price because it is privately held. The most recent known share price comes from its last funding round. Pre-IPO share prices on the secondary market may differ from the last round price depending on supply, demand, and market conditions.
Yes. Accredited investors can indicate interest in Substack shares through UpMarket by filling out the form on this page or creating an account at upmarket.co. All pre-IPO offerings are subject to availability and require a $50,000 minimum investment. UpMarket is a FINRA-registered broker-dealer and has brokered more than $500M in alternative investments since 2019.
Pre-IPO investments carry significant risks. Substack shares are illiquid, meaning there is no public market to sell them quickly. There is no guaranteed exit timeline or return. The investment is speculative in nature, and investors should be prepared for the possibility of total loss. Valuations of private companies can fluctuate substantially between funding rounds. Investors should consult their financial advisor and review all offering documents before investing.
In a pre-IPO transaction, accredited investors purchase shares from existing shareholders (such as employees, early investors, or other holders) through secondary market platforms. The company itself does not issue new shares in these transactions. UpMarket facilitates these trades as a FINRA-registered broker-dealer, handling compliance, documentation, and settlement on behalf of both parties.
There are two primary exit paths for pre-IPO holdings: selling your shares on the secondary market to another buyer, or holding until the company completes an IPO or is acquired. Both paths are subject to transfer restrictions, company approval (right of first refusal), and market conditions. The timing of any exit is unpredictable, and investors should plan for a multi-year holding period.
The minimum investment for most pre-IPO offerings on UpMarket is $50,000. This amount may vary depending on the specific offering and share availability. There are no fees to create an UpMarket account or browse available investments. Investors only pay transaction-related fees when they complete an investment.
UpMarket's valuation estimate of is derived from a proprietary model that incorporates multiple data sources: funding round data (Caplight), revenue estimates (Sacra), secondary market pricing, and public company comparables. The model applies a private company discount to the public comp multiple to account for illiquidity and information asymmetry. This estimate is not investment advice and may differ substantially from the price at which shares actually trade.
Substack runs a private subscription publishing platform for newsletters and paid posts, and reported $29M in 2023 revenue, up 50% year over year; it was last valued at $1.1B — accredited investors can access Substack stock through UpMarket.