At the time of writing, there are three payment levels within MailChimp:
1. Free forever (for up to 2,000 subscribers).
2. For lists over 2,000 (or if you wish to avail yourself of the standard paid for features) then payment starts at US$10 dollars per month. See: https://mailchimp.com/pricing
3. MailChimp Pro includes multi-variant testing and comparative reports that deliver detailed insights into subscriber habits and product preferences. Advanced subscriber segmentation allows you to target the right people for your MailChimp campaigns. The current cost of MailChimp Pro is US$199 + monthly plan charge.
MailChimp Pro enables more targeted sending. ‘Advanced Segmentation’ enables you to segment with more conditions and apply combinatorial logic with nested conditions. You can create segments that combine both ‘Any’ and ‘All’ logic in one segment. With MailChimp’s standard Segmentation facility, you are limited to 5 conditions. This restriction is lifted for Pro account holders.
It does take a little while to get your head around the functionality of MailChimp Segmentation. If you have been using MailChimp for a while, it would be helpful if you are already using Segmentation. Within MailChimp Pro, there are more options available and I recommend that you take some time to learn how to use it.
You can test different Subject lines, From names, and Contents within MailChimp Pro using up to eight Campaigns. At the time of writing, MailChimp is the only email marketing platform that offers this functionality.
MailChimp Pro Comparative Reports
Comparative reports enable you to tailor the way you that you interact with your data. Insights are provided with regards to subscriber behaviour. You can compare a set of MailChimp campaign results in order to evaluate performance over time. Having sent a campaign, you can create advanced segments within your reports. Recurring reports can be sent to colleagues via email automatically. See: https://mailchimp.com/features/comparative-reports
You can take campaigns, group them together and look at aggregate statistics. You can then monitor the performance of these campaigns over time and see how your chosen campaigns perform against a baseline.
Choose campaigns for comparison purposes using filters such as folder, keyword, timeframe or days sent. You can then view the performance of each campaign over time. Alternatively, you can select MailChimp campaigns that fit your criteria in order to compare against each other/all within a single screen.
In general terms, MailChimp Pro is for enterprises with larger lists who take their email marketing seriously. It allows you to select subscribers on a more granular level and communicate with them via MailChimp campaigns or Facebook advertisements.
If you need help, I offer MailChimp training services.