Chase issued an apology on its website Thursday in the wake of the online banking service failing during the week's first half due to a technical problem.
“We are sorry for the difficulties that recently affected Chase.com, and we apologize for not communicating better with you during the issue,” the statement read on the site.
Online bill payments scheduled for Sept. 13, 14 and 15 were processed Wednesday night, according to the statement.
Chase said it will refund late fees customers may have incurred during payment processing as a result of the technical problem.
The online banking service said it intends to prevent future technical glitches.
"This was not the level of service we know you expect, and we will work hard to serve you better in the future and to communicate with you better if a situation like this should arise again," Chase said on its site.
Shares of JPMorgan Chase closed slightly higher at $40.99 Thursday.