Here are some highlights that might affect your Mailchimp account if you are close to moving to over 2,000 contacts in your Free Plan.
7B. Audience and Archiving
You may have several types of contacts in your Mailchimp account, but only contacts that you can engage through the Service count as contacts in your “audience” for purposes of your Monthly Plan or Free Plan. Subscribed, unsubscribed, and transactional (or e-commerce) contacts count towards your audience. Cleaned, pending, reconfirmed, deleted, and archived contacts do not count towards your audience. You may elect to archive contacts at any time, but any profile changes for an archived contact (whether initiated by you, the contact, or an integration) will automatically unarchive that contact. You cannot engage in any activity through the Service with archived contacts unless and until they are unarchived. If a contact is unarchived, it will immediately count towards your audience for your current billing cycle and any future billing cycles unless and until archived again.
8. Free Plans
If you use the Service under the free plan (“Free Plan”) and you want to go over the Free Plan limits, you’ll be required to upgrade your account to, and select and pay for, a Monthly Plan. Monthly Plans are described in Section 7A above. If you exceed your Free Plan limits, or otherwise upgrade your account to a paid Monthly Plan, you’ll only be provided one complimentary downgrade to the Free Plan (provided your sending volume and audience numbers drop down to the Free Plan limits again). If you go over the limits for the Free Plan more than once, you’ll no longer qualify for the Free Plan, even if your future sending volume and audience numbers are within the limits of the Free Plan.