Shares were up 1.34% to $85.49.
Dimon, 63, said in a message to the company's employees that he is working remotely, following emergency heart surgery on March 5 to repair a tear to his aorta.
"I want to thank you all for the sweet well wishes you sent my way after my emergency surgery," he said. "I have been recuperating well and getting stronger every day, and I am happy to be back to work this week — albeit working remotely like so many of you."
Dimon acknowledged the challenges the company is facing due to the coronavirus, saying he recognized "the hardship many of you are enduring as you work so hard to protect our fellow citizens while focusing on supporting the global financial system that is so essential for everyone."
"You’ve risen to the challenge each and every day and remain steadfast in helping our clients, customers, communities and countries across the globe," he said. "You should know how grateful and proud I am of what you all have been accomplishing."
Dimon, has been CEO of JPMorgan since the end of 2005, also thanked Daniel Pinto and Gordon Smith, co-presidents and co-chief operating officers of the financial giant, who were named to lead the company during Dimon’s recuperation, along with the company's operating committee and senior leaders "for the extraordinary leadership they have shown in the most difficult of circumstances.
Like so many companies, JPMorgan Chase has struggled with the devastating impact of the pandemic and last month the bank instituted a firm-wide hiring freeze.
Citing people familiar with the matter, Bloomberg reported that corporate and investment banking, consumer and asset- and wealth-management groups have been asked by the bank to review job postings and pull listings for roles that aren’t immediately needed.