1. Contacts who are sent a newsletter are tagged with the corresponding month and year. For example, their name may have a “June 2020 newsletter tag.” 
2. To find contacts that have received the newsletter, click “Contacts” at the top of your toolbar.
3. Find “Search by Tag” on the right side of your screen. 
4. Search the relevant tag (e.g. “June 2020 newsletter”).
5. You will be shown a list of contacts with the specified tag.