Export Substack Subscribers (and Move Them to Kit)

The problem

Many writers use Substack for publishing and a separate tool for everything else. Two of them describe the gap:

"Substack is where people subscribe to my newsletter. Kit is where my actual marketing lives." (LinkedIn, 2026-06-16)

"Is there really no easy way to sync your subscribers to an external email platform like MailerLite?" (r/Substack, 2026-07-26)

This is one of the most common integration complaints. In our October 2026 review of public Reddit, forum and community threads, "nothing syncs out" (to Kit, MailerLite, ActiveCampaign, CRMs or ad pixels) came up in 15 of the 65 writer sources. Examples include a Make community thread and an r/Substack thread.

The fix starts with Substack's own CSV export, which is quick. Moving the list somewhere useful without hurting deliverability or breaking consent takes more care. This guide covers both, as of October 2026, using Substack's help centre and the import rules published by Kit, Mailchimp and HubSpot.

How do I export my Substack subscribers?

Substack's export help article gives these steps:

1. Open your publication dashboard and go to Subscribers.
2. Scroll to "All subscribers".
3. Click the three dots above the list and choose Export.
4. Choose all columns or visible columns only.
5. Download the CSV. The dashboard guide says you can fetch it with "Download last export" (Substack Help).

To export only part of the list, apply a filter first (for example paid only, or a signup date range), or tick the checkbox next to specific emails, then export. When filters are on, Substack asks whether you want the entire list or only the filtered list.

The full publication export (Settings → Exports) also contains a subscriber list alongside your posts. Our Substack backup guide covers that route. Going the other way, into Substack, is covered in adding subscribers to Substack.

What columns are in the Substack subscriber CSV?

Substack doesn't publish a fixed column list, and the columns depend on which option you pick. Here is what the help centre documents:

Option	What Substack says it contains	Source
Visible columns only	"the default columns (such as the date someone subscribed and their type of plan)" plus your filters	Export help
All columns	Columns that "can vary from when the subscriber last opened an email to their individual post views"	same
Names	Not available: "It's not currently possible to export a file with subscriber names."	same

The dashboard guide describes the columns you can display, and these are the ones you're likely to see in an all-columns export (Substack Help):

Dashboard column	Meaning (Substack's wording, shortened)
Subscription type	free, paid, founding, gift or comp, plus monthly or annual
Activity	how active the subscriber was in the last month, including opens and web views
Revenue	money paid, not counting refunds
Email opens (7 days, 30 days, 6 months)	how often your emails were opened
Subscription source (free)	how they arrived before subscribing, for example the app or Google
Paid upgrade date	most recent free-to-paid conversion

Always open your own file and check the header row before mapping fields. Header names can change without notice.

Readers who subscribe in the Substack app are included. Substack says "you'll get their email address just like normal" and that you can "export them at any time" (Substack Help).

How do I move my Substack list to Kit, Mailchimp or HubSpot?

You can: the Terms of Use say you own what you create, "That includes publications, subscriber lists". Each destination accepts a CSV and asks you to confirm consent:

Destination	File	Consent rule (quoted)	Useful detail
Kit	CSV with an email column and a header row	"Each person on your list is required to have provided their permission to receive your marketing emails" (Kit)	Imports "replace any existing data … with the data you provide", including blanks; existing tags are kept (Kit)
Mailchimp	CSV or TXT	"be sure that you have permission to send them email marketing content" (Mailchimp)	You can tag every contact in the import at the "Continue to tag" step
HubSpot	Spreadsheet import	Tick consent "to agree that contacts expect to hear from you and that your import file does not include a purchased list" (HubSpot)	With privacy settings on, you set a legal basis per import

A safe mapping recipe

1. Export all columns from Substack.
2. In a spreadsheet, keep the email column, the subscription-type column and the date subscribed. Drop activity columns your new tool can't use.
3. Add a tags column, for example substack-free or substack-paid, so you can segment later. Kit expects tags separated by commas in one column.
4. Remove anyone who unsubscribed or whose emails bounce, if your file marks them.
5. Import into a new tag or list rather than your main audience, so you can watch engagement before merging.
6. Never upload blank columns over existing Kit data, because blanks overwrite.

Paid subscribers are a separate problem. Moving their emails does not move their billing. Payments run through your Stripe account, so plan a paid migration with your new platform's documentation. Don't charge anyone twice.

Will moving my list hurt consent or deliverability?

Consent is the line that matters. Every destination above asks you to confirm it, and Kit is blunt: "If you aren't certain you have their permission, stop here." (Kit). People who subscribed to your Substack agreed to hear from your publication. Tell them you're moving and give them a one-click way out.

Deliverability is the practical risk. Mailbox providers watch complaint rates. Google asks senders to keep the spam rate reported in Postmaster Tools below 0.3% and to support one-click unsubscribe for marketing mail (Google Workspace Admin Help). A cold list mailed all at once from a new domain can cross that line quickly. To reduce the risk:

• authenticate your new sending domain (SPF, DKIM and DMARC) before the first send;
• send first to your most engaged readers, using Substack's activity and opens columns to pick them;
• make the first email an announcement with a clear unsubscribe link;
• stop and investigate if complaints spike.

How do I keep Substack and Kit in sync?

Not natively. The writer quoted at the top built her own weekly routine, and named its weak spot: "It's the people who slipped through the weeks I forgot." (LinkedIn). As of October 2026 Substack offers no subscriber webhooks and no Zapier app, so the green route is a scheduled re-export:

1. Each week, filter Subscribers by signup date since your last export.
2. Export visible columns.
3. Import the new rows into your other tool under a tag.

Moving people between tools also loses metadata. One writer moving readers the other way, from Kit to Substack, put it this way: "The one thing I'm still trying to get used to is the idea of losing all my metadata like tags" (r/Substack). Keep your tags in the CSV so you can rebuild them.

The newsletterapi analytics API reads your own exports and returns clean JSON, including who is new since the last export. The backups API covers the archiving side. To get access to either, email hello@newsletterapi.io.

What mistakes should I avoid when moving my list?

Mistake	Why it hurts	Fix
Importing everyone as "subscribed" without telling them	Complaints, then a blocked sender	Announce the move; import to a tag first
Mapping blank cells over existing data	Kit overwrites fields with blanks	Delete empty columns before import
Expecting names in the export	Substack doesn't export them	Ask for names in a welcome survey
Moving paid emails and assuming billing follows	Billing stays with the Stripe setup Substack uses	Follow your new platform's paid migration guide
Emailing the CSV around	It's personal data	Store it encrypted; delete old copies