Your advice on merging subscribers

Hi, I have just started a brand new newsletter with Ghost Pro. I have been slowly collecting subscribers from a course I teach over on Mailchimp, but have really been bad at taking advantage of sending regular mail to that audience. I have 650sh subscribers to that list, and havent regularly communicated with most of them.

I am hesitant to add all 650 subscribers from Mailchimp to Ghost, as Im on the starter plan with 500 members, and dont want to add a bunch of potentially inactive or unengaged accounts

Is there a way I should do this and then easily cull the list to engaged users?

Alternative options:
Send a newsletter to that list and tell them to find me here, but I feel like that will have a very low conversion rate as it requires a lot of extra steps for them.

Send a newsletter on Mailchimp mimicing ghost and see if they sign up, but its a lot of manual work and might confuse them as to why they need to sign up if theyre already getting emails.

Would love your advice!

It’d be possible to use the API to send each user a magic link (which they have to click to get added to Ghost), but those links expire after 24 hours, which is likely not long enough for some newsletters’ readership.

It’d be possible to write some custom code that generates an alternate ‘magic link’ (hosted separate from Ghost) for each email address, and then you’d just put a “click here to sign up for the newsletter” button in your final Mailchimp missive. That link would go to a cloud function that’d validate that the user was who they said they were (because everyone gets a unique link) and get them logged into Ghost and subscribed for email. But that’s going to take custom work, and you might not want to go there.

You could send a few messages to the Mailchimp list and then you’d have stats for who isn’t engaged (with the big caveat that open rates are often misleading) and could skip importing them.

If your list is clean and your users are double opt-in, then you could import them to Ghost, start sending them emails, and cull whoever unsubscribes (some will) or isn’t opening or visiting the site. You might want to lead off with an email explaining what’s going on (we moved!) and clear directions for how to unsubscribe if they don’t want the newsletter.