Want an email referral program? Don't use Substack

Want to add a referral program to your newsletter? Don't use Substack.

Manuel Frigerio

Everyday we get emails from people on Substack asking us how they can add a referral program to their newsletter.

This, of course, doesn’t surprise us; with other acquisition channels either taking a very long time to show ROI (like content marketing) or getting very expensive (like paid ads or sponsorships), a referral program is the best way to grow an engaged audience in a scalable, affordable and low-effort way, as proved by thousands of successful newsletters, from The Morning Brew and TheHustle to James Clear, Lifespan and Influence Weekly.

Unfortunately, they usually don’t like our answer: Substack is (currently) the worst email platform for running a referral program.

In this post I’m going to show you why, if you really want to run a referral program, you should switch to a different email platform.

What it takes to add a referral program to a Substack newsletter

A referral program looks very simple from the outside; you give your subscribers a referral link, they share it and invite their friends and you reward them for it.

However, the platform that handles the referral program has to deal with quite a lot of complexity behind the scenes, like:

  • making sure that each referral link is unique
  • storing the referral link in the ESP (email service provider, i.e: MailChimp)
  • making it easy to give your subscribers their referral link and tell them how many referrals they’ve got
  • tracking and attributing referrals to the right subscriber
  • and handling rewards distribution

When you use a different ESP (e.g: MailChimp, ConvertKit, Campaign Monitor, etc), all the above is automatically handled by SparkLoop without you having ever to worry about it.

With Substack things are much more complicated.

Let's start with generating unique referral links, the most important component of every referral program.

Since there’s no way to automatically generate referral links on Substack, you must use a 3rd-party (like ReferralHero or Viral Loops) that gives you a widget that you embed on your website. People need to sign up through the widget and NOT your sign up forms.

This is where things start to get tricky.

A widget must be embedded on a page but Substack... doesn’t have pages.

Hence, you have to have a separate website (Substack also doesn’t support custom domains), create a page (coding skills required) and embed the widget in it.

Next, these widgets are not connected to your Substack account (Substack doesn’t support third-party integrations, nor it has APIs). Anyone who signs up through these widgets has to be manually imported into Substack as well.

What if someone unsubscribes from your Substack newsletter? No way to automatically notify your referral platform about that. You have to manually remove them.

To add insult to the injury, these referral platforms can only track referrals if people sign up through their widgets. This means that someone who clicks a referral link (and thus lands on the page with the widget), leaves that page and signs up through a signup form on a different page will not be tracked as referral.

In a nutshell, it is “technically” possible to add a referral program to a Substack newsletter but… it requires a lot of work, coding skills and it’s a very manual process.

Your email list is effectively in two places that don’t talk to each other and you constantly have to manually import/export data from one platform to the other to keep things synced.

Packy McCormack, author of the highly popular newsletter Not Boring, who currently has a referral program with his Substack newsletter, describes this situation better than anyone else:

“[...] It's a process of downloading the list at the end of each day, dumping that into a Google Sheet, and then taking the emails from that Google Sheet and putting them back into Substack.”

Poor User Experience

Even if you decide that you’re willing to go through all the hoops, there’s still one important part of the user experience that you might want to consider. 

See, the secret of a successful referral program is to make it very easy for people to share their referral link.

And right now, there’s no way to do that with Substack.

Ideally, things like the referral link and the number of referrals would be stored in custom fields so that you can reference them in your emails and create something like this:

The above example is from one of our customers, James Clear.

Imagine receiving this email; all you need to do to share the link is click on the “Click to share” button or copy your referral link and paste it on Facebook or Twitter.

Unfortunately, another big limitation of Substack is that it doesn’t have custom fields which means you can’t store things like referral links or the number of referrals in Substack.

So what do you do? Your only option is to give your subscribers a link to the landing page with the widget in it so they can enter their email address to get their referral link.


The drop-off will be huge and most people will give up before sharing their referral link.

A better way

Fortunately there’s an easier and better way.

Most email platforms don’t have the limitations Substack has (no integrations, no APIs, no custom fields, etc) and thus can be integrated with referral platforms much more easily.

And if you’re going to switch email platforms for your referral program, make sure you use the best referral platform.

SparkLoop was designed specifically for newsletter creators like you and we have already helped hundreds grow 10-30% faster a month.

Smart newsletter and course creators choose SparkLoop because...

  • Native integration with 5 ESPs (ConvertKit, MailChimp, Campaign Monitor, MailerLite and Active Campaign) and counting…
  • No coding required.
  • No widgets. You keep using the same sign up forms that you currently use
  • Referrals are automatically tracked across all your signup forms
  • All data is automatically synced between SparkLoop and your email platform (including unsubscribers). No need to manually export/import files.
  • All data is automatically stored in your email platform’s custom fields so your subscribes can easily share their referral link from your emails
  • Automated distribution of rewards
  • Hosted referral hub page

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