How to switch podcast hosting platforms without losing subscribers
If you're moving from one podcast host to another, you won't lose subscribers if you do a 301 redirect from your old RSS feed to your new RSS feed.
Once a redirect is in place on your old RSS feed, it will automatically forward your existing subscribers to your new host. They won't even know you've switched providers!
On Reddit, a user asked:
I am wanting to switch podcast hosting services. When I switch, will all the podcast directories upload new episodes when I put the link to my new RSS feed into the RSS feed redirect of the old host? For instance, after I switch services and upload a new episode via the new hosting service, will Spotify, iHeartRadio, Google Podcasts, Stitcher etc have the new episode listed?
Here's how to switch your host without losing subscribers on Apple Podcasts, iTunes, Spotify, Google Podcasts, and Stitcher.
Step 1: Import your podcast to your new podcast hosting provider
Most podcast hosting providers, like Transistor, will have an import/migration wizard.
Copy the RSS feed URL from your old podcast hosting provider.
Paste it into the import tool for your new podcast host.
Verify ownership of the podcast
These migration tools will copy all of your MP3 files, podcast artwork, and show notes, over to your new podcast hosting provider.
Step 2: Forward your podcast's old RSS feed to your new RSS feed
Podcast players (like Apple Podcasts and Spotify) pull your podcast's information from your RSS feed. A 301 redirect lets these apps know where your new feed is hosted.
On most hosting platforms, doing a 301 redirect from your old RSS to your new RSS is easy. Here's what it looks like on Substack:

Here's how to forward your old RSS feed on different podcast hosting platforms:
On Substack: go to the "Podcast" menu, click on the "Settings" button, and scroll to the bottom until you see the "Redirect RSS feed" button.
On Simplecast: go to "Podcast settings" and scroll to the bottom until you see "Advanced settings."
On Libsyn: go to your Dashboard and click on "Destinations." Click "Edit" for the "Libsyn Classic Feed." Click "Advanced Options" at the bottom of the page. Paste in your new Transistor feed URL in the "Redirect Feed to this Web Address" input box.
On Buzzsprout: go to "My Profile" and then to the "Cancel/Redirect Podcast" tab. You should see an option that says "Redirect Your Podcast Feed."
On Transistor: go to "Settings," and scroll down to "Advanced Settings." There, you'll see "Permanent Redirect (301) of your RSS Feed to another URL."

Once you've set a 301 Permanent Redirect to your new feed, Apple Podcasts and other directories will pick up the change automatically so your audience won't even notice.
(Want to migrate your podcast to Transistor from Simplecast, Libsyn, or Buzzsprout? Read this guide).
Step 3: update your RSS feed URL on Apple Podcast Connect
Marco Arment, the creator of Overcast, notes the importance of Apple Podcasts:
The iTunes Store’s Podcasts directory is the only one that matters, and being listed there is essential for podcasts to be easily found when searching in most apps.
Apple should follow the 301 redirect to your new podcast feed, but you can also update your feed address on Apple's Podcast Connect. Just log in, find your show, and paste in your new feed URL.

Step 4: update your RSS feed on Spotify, Stitcher, and Google Play
While most apps and directories (like Overcast, Pocket Casts, Castro, Breaker) will scrape Apple's podcast directory, there are a few other "walled gardens" that you'll need to update manually.
You can do this yourself on Stitcher, Google Podcasts, and on Spotify.
Step 5: wait a few weeks before deleting your account!
After you've redirected your old RSS feed to your new feed, it's best to wait two weeks before you delete your old hosting account. Also, it can take 24-48 hours for Apple to propagate your new feed on their platform. Be patient!