HarborOne Credit Union will hold a special meeting today for members to vote on a proposed conversion to a mutual cooperative bank charter.

HarborOne executives announced the plan this time last year, shortly after the credit union left the Massachusetts Credit Union League and the Credit Union National Association. At that time, its board of directors voted unanimously to pursue the charter change.

While the credit union’s leadership has largely kept mum about the proposed change since it announced its intent, the credit union has previously said that it wants to convert to a bank charter so it can have greater flexibility to expand its customer base and access to additional capital.

The $1.9-billion institution has about 150,000 members, but only those who were members for three months as of Feb. 15, 2012 are eligible to vote. Results will not be final until an independent inspector tallies the ballots, which should be completed within 10 days, said James Rice, HarborOne’s vice president of marketing.