As far as I can tell, there is no exception under the MA wiretapping law to allow for businesses to record phone calls without both parties' consent. The one possible exception is for financial institutions, and even then, notice has to be provided regularly.
B. Definitions. As used in this section: ...
The term ''interception'' means to secretly hear, secretly record, or aid another to secretly hear or secretly record the contents of any wire or oral communication through the use of any intercepting device by any person other than a person given prior authority by all parties to such communication; ...
The term ''person'' means any individual, partnership, association, joint stock company, trust, or corporation, whether or not any of the foregoing is an officer, agent or employee of the United States, a state, or a political subdivision of a state. ...
The term ''financial institution'' shall mean a bank, as defined in section 1 of chapter 167, and an investment bank, securities broker, securities dealer, investment adviser, mutual fund, investment company or securities custodian as defined in section 1.165-12(c)(1) of the United States Treasury regulations.
- Interception, oral communications prohibited. Except as otherwise specifically provided in this section any person who willfully commits an interception, attempts to commit an interception, or procures any other person to commit an interception or to attempt to commit an interception of any wire or oral communication shall be fined not more than ten thousand dollars, or imprisoned in the state prison for not more than five years, or imprisoned in a jail or house of correction for not more than two and one half years, or both so fined and given one such imprisonment. ..
Permitted interception of wire or oral communications. It shall not be a violation of this section: ...
f. for a financial institution to record telephone communications with its corporate or institutional trading partners in the ordinary course of its business; provided, however, that such financial institution shall establish and maintain a procedure to provide semi-annual written notice to its corporate and institutional trading partners that telephone communications over designated lines will be recorded.
Given the complicated nature of interstate wiretapping laws, it would be well worth your while to consult with legal counsel before you start recording callers from Massachusetts (or, indeed, anywhere out of your own state.) The most important quote in that article is, I think, this one:
[O]ur research led us to conclude that the law is still developing in this area and that much uncertainty remains.