Substack was founded in 2017 by Chris Best, the co-founder of Kik Messenger; Jairaj Sethi, a head of platform and principal developer at Kik Messenger; and Hamish McKenzie, a former PandoDaily tech reporter.[10][11] Best and McKenzie describe Ben Thompson's Stratechery, a subscription-based tech and media newsletter, as a major inspiration for their platform.[5] Best acts as CEO of the company.[12][13]
In 2019, Substack added support for podcasts and discussion threads among newsletter subscribers.[14][15]
By November 2021, the platform said it had more than 500,000 paying subscribers, representing over one million subscriptions.[16]
Substack announced in January 2022 that it would begin private beta testing of video functionality on its platform.[16] In November of that year, they launched Substack Chat where content creators could create private group chats with subscribers.[6]
Also in 2022, the company launched the Substack Reader app for iOS, followed by an Android version six months later.[17][18]
In April 2023, Elon Musk spoke with Substack's leadership about purchasing the platform, but the proposal was not accepted.[19] That same month, Substack implemented a Notes feature, which allows users to publish and repost short-form content. This microblogging feature was compared to Twitter, and many outlets considered it to be a response to changes at Twitter under the ownership of Elon Musk.[20][21] The launch of Substack Notes resulted in criticism by Musk, and Twitter began censoring links to Substack on its platform.[22][23][24]
In November 2023, Substack introduced new video creation and editing tools, and content creators started launching original shows on the platform.[6][25]
In April 2024, Substack partnered with Spotify to allow podcasters to distribute episodes on both platforms and added new editing features for podcasts.[26] In June 2024, Substack announced a year-long development initiative for TikTok creators called Creator Studio,[27] and also added five-minute video capabilities to their chat function.[28] Video was also added to Notes.[29][30]
By November 2024, Substack had 4 million paid subscriptions.[31]
Substack added livestreaming options for creators in September 2024.[32][25] Following this and the restrictions on TikTok in the United States, Substack announced the ability to post and monetize videos directly through the Substack app in February 2025.[29] In March 2025, Substack announced that it had 5 million paid subscriptions.[33]
Substack users include journalists, subject-matter experts, and media platforms.[34][35][36] Among the high-profile writers to have used the platform are Pulitzer Prize-winning journalist and author Glenn Greenwald; the Nobel laureate and economist Paul Krugman; Seymour Hersh; culture critic Anne Helen Petersen; music essayist Robert Christgau; and food writer Alison Roman.[37]The New York Times columnist Mike Isaac argued in 2019 that companies like Substack see newsletters as a more stable means to maintain readers through a more direct connection with writers.[12] In 2020, The New Republic said there was an absence of local news newsletters, especially in contrast to the large number of national-level political newsletters.[38] As of late 2020, large numbers of journalists and reporters were coming to the platform, driven in part by the long-term decline in traditional media (there were half as many newsroom jobs in 2019 as in 2004).[39] Around that time, The New Yorker wrote that while "Substack has advertised itself as a friendly home for journalism, ... few of its newsletters publish original reporting; the majority offer personal writing, opinion pieces, research, and analysis."[40] It described Substack's content moderation policy as "lightweight", with rules against "harassment, threats, spam, pornography, and calls for violence; moderation decisions are made by the founders".[40]
Authors can decide to make subscribing to their newsletter free or paid, and to make specific posts publicly available to non-subscribers.[40] As of 2020[update], the minimum fee for a subscription was $5/month or $30/year,[40] and Substack usually takes a 10% fee from subscription payments.[36][10] Substack earns no revenue from advertisements placed by publishers.[39] In February 2019, the platform began allowing creators to monetize podcasts.[52] Substack reported 11,000 paid subscribers as of 2018, rising to 50,000 in 2019.[52]
In 2019, the site provided a fellowship to some writers, which included a $3,000 stipend and a one-day workshop in San Francisco. The decline of sports-oriented publications such as Sports Illustrated, Deadspin, and SB Nation, coupled with the onset of the COVID-19 pandemic, led to a surge in sports journalists moving to write on Substack in 2019 and 2020. Substack competes with subscription site The Athletic in this submarket, so McKenzie says the company recruits less strongly in that market.[10] In 2020, following the onset of the COVID-19 pandemic, Substack extended grants of $1,000–$3,000 to over 40 writers to begin working on the platform.[10] Substack expanded into comics content in 2021 and signed creators including Saladin Ahmed, Jonathan Hickman, Molly Ostertag, Scott Snyder, and James Tynion IV, paying them while keeping their subscription revenue. After their first year, Substack will take 10 percent of subscription revenue.[45]
The Substack founders reached out to a small pool of writers in 2017 to acquire their first creators.[11] Bill Bishop was among the first to put his newsletter, Sinocism, on Substack, providing his newsletter for $11 a month or $118 a year with daily content.[5] As of 2019, Bishop's Sinocism was the top paid newsletter on the service.[52] By late 2020, the conservative newsletter The Dispatch claimed the title of top Substack user, with more than 100,000 subscribers and over $2 million in first-year revenue, according to founder Steve Hayes.[39] In May 2021, Substack acquired Brooklyn-based startup People & Company.[55] In August 2020, Substack reported that over 100,000 users were paying for at least one newsletter.[54] As of August 2021, Substack had more than 250,000 paying subscribers and its top ten publishers were making $7 million in annualized revenue.[56] In April 2022, The New York Times reported Substack may be valued at $650 million.[57] Substack dropped an effort to raise money in May 2022.[58] The company had aimed to raise between $75 million and $100 million.[58]
In March 2021, Substack revealed that it had been experimenting with a revenue sharing program called Substack Pro that paid advances for writers to create publications on its platform,[4] but received criticism for not disclosing which writers were part of Substack Pro.[59] This program ended in 2022.[60]
Substack provides legal advice to its writers through its program Substack Defender. Lawyers provide a legal review of stories before they are published, and provide advice surrounding cease-and-desist letters related to writers' work. Substack has committed to covering up to $1 million in fees for cases accepted by Defender lawyers.[56] The program was expanded in 2025 including a partnership with the Foundation for Individual Rights and Expression.[61]
On July 28, 2020, Substack accidentally exposed users’ email addresses by putting them in the "cc" field instead of "bcc" in a privacy policy update email regarding the California Consumer Privacy Act. The company acknowledged the issue on Twitter.[62]
In 2020, popular platforms such as Twitter, Facebook, and YouTube began restricting or removing accounts that they claim spread COVID-19 misinformation, and some prominent authors accused of spreading misinformation have moved from those platforms to Substack. The Washington Post mentioned Joseph Mercola and Steve Bannon as conspiracy theorists who have moved their online presence to Substack.[63]
In January 2022, the Center for Countering Digital Hate accused Substack of allowing content that could be dangerous to public health. The Center estimated that the company earned $2.5 million per year from the top five anti-vaccine authors alone.[63] The three founders affirmed their commitment to minimal censorship in a blog post in response.[64]
Substack faced further criticism in November 2023 for allowing its platform to be used by white nationalists, Nazis, and antisemites.[65] In an open letter, more than 100 Substack creators threatened to leave Substack[66] and implored Substack's leadership to stop giving bigotry a platform.[67] In response, Substack CEO Hamish McKenzie said that the company will continue to allow the publication of extremist views because attempting to censor them would make the problem worse.[68][69] Creators like Casey Newton,[70][71][72]Molly White, and Ryan Broderick left the platofrm as a result.[73]