The relationship between “rule and exception” is one of the fundamental issues in the systematic analysis of civil law, which finds a particular manifestation in the law of contracts through the principle of the binding force of contracts. This principle, as the governing rule over contractual relations, ensures stability and certainty in transactions. Nevertheless, the existence of institutions such as rescission, automatic termination, nullity, non-enforceability, and mutual dissolution (iqālah) raises questions regarding the scope and nature of the exceptions to this principle. The purpose of this study is to clarify the precise relationship between rule and exception within the framework of the binding force of contracts and to address whether these exceptions undermine the rule or can be analyzed and justified within its structure. The research adopts a descriptive-analytical method with a conceptual approach, drawing on Islamic jurisprudential sources, provisions of the Iranian Civil Code, and doctrinal legal analysis. The findings indicate that the exceptions to the principle of binding force, contrary to traditional views, are not merely instances of deviation from the rule, but rather constitute internal mechanisms designed to ensure contractual justice, eliminate imbalance, and adapt to economic and social realities. It is concluded that the relationship between rule and exception in this context should be understood as complementary and functional rather than oppositional; in such a way that the exceptions, while preserving the core of the principle, enable flexibility and enhance the efficiency of the law of contracts.