More than a third of senior decision makers surveyed by open data platform Moneyhub said they had limited or no knowledge of the new legislation.
Only a fifth of firms had projects in place to meet the 2023 deadline while around a quarter are developing plans.
Almost half of firms are investing in technology to deliver more personalised communications, the study found.
The FCA’s new regulations mean customers must receive communications from financial services firms that they understand.
Moneyhub said without Open Finance providing the consent-driven data insights businesses will struggle to gain the information they need to meet their obligations under the duty.
Samantha Seaton, chief executive of Moneyhub, said: “There are no excuses left, businesses must ensure they understand their customer completely in order to offer products and services that fit their circumstances throughout the entire duration of their relationship.
“And the only way this is possible is with an ongoing holistic view of their customer’s financial universe. Open Finance truly holds the key for firms to meet Consumer Duty. But to see Open Finance’s role as solely a solution to a problem is a mistake. It is also an opportunity.
“By better understanding your customer, it means you can offer super relevant, appropriate products and services, and ultimately create stronger relationships and build loyalty. Smart, forward looking businesses will seize this moment and reap the benefits of truly understanding their customer.”
