Substack has been the topic of a lot of conversations lately. Some people on the platform encourage everyone they know to join them immediately because the platform offers several tools to help grow your following. Others refuse to use Substack and harshly criticize those who do, accusing them of being devoid of moral values because it espouses a decentralized content moderation policy and thus permits content that many find repugnant.

But what is Substack?

Substack is a popular subscription-based newsletter publishing platform used by journalists, writers, and experts to share articles, podcasts, and videos with their subscribers. Those who use the platform (referred to as “Substackers”) can adopt a tiered subscription plan that allows them to share all their content for free or limit access to some or all of their content to paid subscribers. Substack is based on a shared-revenue model, which means it takes a commission on all subscription income. The more money Substackers make, the more money Substack makes.

Substack was the first platform to offer a shared-revenue model and to make it easy for writers to create a subscription-based newsletter. When it first came on the scene in 2017, Substack actively recruited journalists and other well-known writers to build their digital home on the platform. Since then, Substack has refined its built-in social network and recommendation engine, making it even easier for Substackers to find their audience and connect with one another.

Substack’s content guidelines are much less stringent than other platforms. Substack explicitly prohibits “credible threats of physical harm” but otherwise states that “critique and discussion of controversial issues are part of robust discourse.” Unfortunately, its approach to content moderation has served as a siren call to conspiracy theorists, hatemongers, and bigots, who can freely share on Substack that which may have gotten them banned elsewhere.

And that is where the content moderation debate begins.

The dark side of free expression.

On November 28, 2023, Jonathan M. Katz published “Substack Has a Nazi Problem” in The Atlantic. He reported finding several newsletters that feature Nazi symbols and promote white nationalism and noted that while Substack has a largely hands-off approach to content moderation, its content guidelines do prohibit hate.

Within weeks of this article being published, more than 200 Substackers, including Katz, published an open letter to Substack’s founders, officially launching the Substackers Against Nazis campaign. The letter starts by asking Substack’s founders why they are “platforming and monetizing Nazis” when it is against the platform’s content guidelines, which state that the platform cannot be used “to publish content or fund initiatives that incite violence based on protected classes.”

Meanwhile, more than 100 other Substackers co-signed a note written by Elle Griffin of The Elysian supporting Substack’s decentralized approach to content moderation. Griffin noted that calls for moderation are calls for “the platform to decide who can say what, and who can be here.” She noted that social media platforms with more robust content moderation policies have struggled to moderate hate speech and misinformation. She applauds Substack’s approach: “Rather than rely on . . . a team of moderators, Substack democratized the process, giving full moderation control to writers.”

It is important to note that hate speech is constitutionally protected under the First Amendment. However, the First Amendment only applies to government entities, not private businesses. Those who publish on Substack (or any other platform) have no constitutional right to free speech on that platform. Private companies can, with few exceptions, restrict whatever speech they wish.

With these opposing viewpoints, the battle lines were drawn.

Hamish McKenzie, one of the co-founders of Substack, responded to these open letters by acknowledging that Substack has “narrowly defined proscriptions” and confirming that the company will “stick to our decentralized approach to content moderation, which gives power to readers and writers.” He also acknowledged that not everyone would agree with their position, but that they welcome a “robust debate about these issues.”

By the new year, several of those who joined the Substackers Against Nazis campaign left the platform, including Casey Newton of Platformer. A well-respected technology reporter, Newton left his job as a senior editor at The Verge in 2020 to launch Platformer on Substack. Substack actively recruited Newton to join the platform, offering a year of healthcare subsidies and ongoing legal support. Over three years, Platformer grew to more than 170,000 subscribers.

On January 11, 2024, Newton shared how and why he decided to leave Substack: “I’m not aware of any major US consumer internet platform that does not explicitly ban praise for Nazi hate speech, much less one that welcomes them to set up shop and start selling subscriptions.” Platformer grew their audience by taking full advantage of Substack’s built-in social network and recommendation engine. These tools are designed to help publications grow and monetize quickly because the more money these publications make, the more Substack makes. “That design demands responsible thinking about who will be promoted and how.”

In July 2025, Substack accidentally sent a push alert promoting one of the pro-Nazi publications on its platform. In an article on Engadget, Substack apologized for the error and noted that the relevant system was taken offline until the problems were addressed.

The next day, Casey Newton of Platformer responded to the story: “[B]ecause the platform invests heavily in social media-style growth hacks, it was inevitable that Substack would actively promote Nazi blogs across various surfaces.”

Substack continues to stand by its decentralized approach to content moderation. Their laissez-faire approach, when combined with the platform’s social network and algorithmic recommendation engine, means that it still permits, promotes, and profits from hate speech. It also still relies on readers to decide what they read and writers to decide what they write.

So, how do you choose a newsletter platform?

When Substack started, it was the only subscription-based newsletter platform designed for those who wanted to adopt a paid subscription model. That’s no longer true. Today, you have options. To determine which option is right for you, ask yourself these five questions:

1. Do you want your newsletter to be a source of revenue? It may sound like a great idea to turn your newsletter into a source of revenue while also using it as a marketing tool, but doing so requires you to build out a second business. A subscription-based publication is a different business model from consulting, and it takes time, energy, and effort to build an audience large enough to ensure that your newsletter is self-supporting. If paid subscriptions are not essential to your business model, you can always stick with a traditional email newsletter service like SendFox, Kit, or Aweber.

2. Do you prefer decentralized content moderation? If you want your newsletter to be a source of revenue, and you prefer to be on a platform that espouses rigorous debate and practices decentralized content moderation, consider Substack. Just be ready to explain your rationale should anyone challenge your decision. Many people have only heard positive things about the platform, while some know only that it is associated with hate groups and right-wing influencers. Few have looked closely at the underlying debate about content moderation and free expression.

3. Do you prefer more robust content moderation? If you want your newsletter to be a source of revenue, and you prefer to be on a platform with a more robust content moderation policy, consider beehiiv. Just make sure you review their Acceptable Use Policy first, especially the sections on content violations and prohibited content. While beehiiv explicitly prohibits content that “incites violence, spreads hate speech, or uses dehumanizing language to target individuals or groups,” it also categorizes any content that “disparage[s] beehiiv or our partners, vendors, or affiliates” as a content violation.

4. Do you want sole responsibility for content moderation? If you want your newsletter to be a source of revenue, and you want to own the platform and be fully responsible for content moderation, consider Ghost.

5. Do you prioritize growth over the debate about content moderation? If you want your newsletter to be a source of revenue, you’re neutral about content moderation, and you want to be on a platform that makes setting up a subscription-based newsletter easy, consider Substack and beehiiv. If you prefer to build your audience through content marketing methods, beehiiv is the better option. If you prefer to build your audience through social networking, especially with other writers on the platform, Substack is the better option.

Regardless of which tool you choose for your email newsletter, it’s important to understand the pros and cons of their business models, content moderation policies, and approaches to growth. In addition to those core questions, make sure you can move off a platform (and take your subscribers with you) should you choose to do so. Also, review any policies related to privacy and copyright.

Your business is built on your reputation and your intellectual property. Protect those assets fiercely.