Customers whose individual Summit accounts were opened prior to September 20, 2017 were opened via different backend system than the one in place today. As a result, these older accounts are not able to support joint ownership.
However, there’s good news: in early 2018, we will allow customers to open up to two Summit checking accounts. Customers that do not have an account that supports joint ownership today will be able to open a new Summit account which does support joint ownership. They can choose to keep both accounts open (one individual and one joint account), or close the one they do not plan to use.