With the magic phrase “automatic de-duping” for a form field you can just paste from excel or a local CSV. Neat.

You can export a list from your CRM, open it in Excel, create a pivot table or perform some other data magic tricks, then copy-paste your results right into this field. We’ll automatically exclude any emails that are not actively subscribed in that MailChimp list.

Segments created by pasting a list are saved as static segments for future use.

Link to MailChimp blog here.