Open Newsletter → Subscribers → Import subscribers. Choose a CSV, TSV or text file, paste addresses, or use both. Record where the list came from and how people agreed to receive the newsletter, then confirm the import. Imported addresses become active without an email confirmation. The result shows how many were imported, already present, invalid, duplicate or suppressed.
Import newsletter subscribers from mobile
Team admins can import consented newsletter subscribers from a file or pasted addresses in the mobile app.