Standard & Poor's last week upgraded Bank of Boston Corp.'s senior debt to A-minus from BBB-plus, based largely on the strength of the banking company's corporate finance and international banking businesses.
S&P also raised the outlook for the bank and its subsidiaries to stable.
The upgrade reflects a continuing trend of improved financial performance, good business-line diversity, and strong market positions at New England's second-largest bank, the rating agency said.
S&P singled out Bank of Boston's focus on national corporate banking and international banking for providing it with a "level of diversification not found at most traditional regional and superregional peers."