Importing subscriber lists from another ESP

We're considering CampaignMonitor as an alternative to our existing ESP. We have 150,000 subscribers. Does anyone know the process to import a list of that size? Specifically, will they have to go through the hassle of opting in again?

Thanks. I searched the community for an answer but all articles were several years old.

aditya31, 2 years ago

I don't think you need to insert it one by one again, but I my self still don't know about this either.

Kris2 Kris2, 2 years ago

You can bulk upload, but you'll probably want to do it in batches of under 10,000.

Undoubtedly, you'll have to go through the data validation checks... so make sure you have:

- evidence of how users have subscribed
- imported all of those that have unsubscribed from the previous list and re-unsubscribed them (or confirm what they are and that you haven't re-uploaded them!)

I have been in love with Campaign Monitor since 2012.

200,000 companies around the world can't be wrong.

From Australia to Zimbabwe, and everywhere in between, companies count on 
Campaign Monitor for email campaigns that drive real business results.

Get started for free