I was asked a question today regarding whether or not a spouse could be considered a cosigner. My initial thought is that the answer would be YES. However, I am not comfortable in giving the answer because I am not sure. If Mr. applied for a loan and didn't qualify: a cosigner was recommended and Mr. brought in Mrs. I would think that if Mr. took all proceeds and Mrs. took none then it could be a cosigner relationship. However, is "what's his is theirs?" Thanks,

12 CFR 227.12

(b)(1) Cosigner means a natural person who assumes liability for the obligation of a consumer without receiving goods, services, or money in return for the obligation, or, in the case of an open-end credit obligation, without receiving the contractual right to obtain extensions of credit under the account.
(2) Cosigner includes any person whose signature is requested as a condition to granting credit to a consumer, or as a condition for forbearance on collection of a consumer's obligation that is in default. The term does not include a spouse whose signature is required on a credit obligation to perfect a security interest pursuant to state law.
(3) A person who meets the definition in this paragraph is a cosigner, whether or not the person is designated as such on the credit obligation.

I see no exemption for a spouse in this definition. Maybe it could be argued that "what's his is theirs" in a community property state, but then again, the signature of the spouse in a community property state would be tricky in this situation unless the spouse had property under "sole ownership".

Using this definition from Reg AA, a guarantor (of a consumer debt) would be defined as a cosinger. This term is not used in the law of instruments.

Excellent point. The original post does not state the context in which this question arose. Discussion so far assumes that the poster is concerned about Reg. AA's coverage. If that is not the case, then Reg. AA is irrelevant and the issue should be evaluated on the basis of the applicable law, regulation, or internal policy.