There were website glitches and call center delays reported on Sunday, the earlier deadline for the 2020 open enrollment, and the extension should help the final enrollment tally, said Evercore ISI analyst Michael Newshel.
"The post-Thanksgiving ramp-up in sign-ups was better than expected, and the momentum bodes well for the key final surge into the deadline this Sunday, December 15," Newshel said in a note last week.
Last year, the number of people who signed up for 2019 health plans fell 4% to 8.5 million people from 2018, but saw a typical trend of last-minute shopping in the final week.
The Centers for Medicare and Medicaid Services runs enrollment for insurance plans created by the ACA, often called Obamacare, through the online marketplace, HealthCare.gov, for 38 states.