American Express (AXP) had the most positive comments online while Bank of America (BAC) fared the worst, according to new research from DigitalMR.

DigitalMR analyzed tens of thousands of online customer comments posted in January about 10 major U.S. banks. The comments were from open access social media platforms and finance-related websites.

DigitalMR said Monday that it found that overall, two thirds of the comments about customer experiences were positive. American Express, Citigroup (NYSE:C) and Bank of America had the highest share of overall mentions but the breakdown of positive to negative comments varied greatly for these banks.

American Express had the highest share of positive comments at 35%, more than twice its share of negative ones. In contrast, Bank of America accounted for the highest share of negative comments at 28%, more than twice its number of positive ones.

Citigroup came in second in both categories with 21% of the positive posts and 17% of the negative comments.

American Express also had the highest net sentiment score at 63% followed by U.S. Bancorp (USB) at 61%. Bank of America came in last out of the 10 banks in terms of net sentiment with a negative 4%.