The problems stemmed from a combination of technical difficulties and heavier than normal traffic to the bank's website, according to spokesperson Tara Burke.
Bank of America is in the process of deploying new online tools for its customers, as well as migrating its online banking to a new platform.
The site's troubles began on Sept. 30, one day after the bank unveiled its $5 monthly fee for debit card customers. That provoked speculation that the bank's website was being attacked by hackers angry about the new charges.
The company declined to comment on the root cause of the problem at that time, and Bank of America always maintained it was not hacked.
On Friday, when CNNMoney first inquired about the outages, BofA's Tara Burke said that the bank was investigating the problem and that the site would soon return to normal.
It's not unusual for a high volume of traffic to bring down a major website. Last month, Target's site was down for prolonged periods when it launched a new line of clothing by designer Missoni.
Bank of America's website suffered a one-day outage in January thanks to a glitch in a routine system change. At the time, the company also fended off rumors that it was being hacked by Wikileaks supporters, after the organization's founder Julian Assange told reporters that a large U.S. bank would be its next subject of leaked documents.
JPMorganChase's online banking service experienced a three-day outage a year ago.
Copyright CNN 2011
