According to law professor Eugene Volokh, marriage is indeed a form of contract.
So marriage is a contract, and has long been described as a contract, but it’s a very peculiar kind of contract that has its own special legal rules. To ask whether marriage is “technically” a contract doesn’t make much sense, because it presupposes a single unique meaning for the term “contract.” If by contract you mean “a contract as typically defined at law,” which is to say a contract that has most of the legal consequences that a typical contract has, then the answer is “largely not,” because marriage contracts have such specialized legal consequences. If by contract you mean “something the law has typically labeled a contract,” the answer is “probably yes,” simply because “marriage contract” has long been a common term. If by contract you mean “a mutual agreement that the law treats as binding as a consequence of the parties’ having agreed to it,” then the answer is “yes.”
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