Full compensation for damages resulting from breach of contractual obligations is one of the fundamental and ultimate goals in legal systems. However, the ability to assess and claim damages based on lost benefits (non-benefits) in the Iranian legal system has always faced serious challenges, ambiguities, and controversies. The divergence of opinions on jurisprudential principles, narrow and literal interpretations of Note 2 of Article 515 of the Code of Civil Procedure, and practical difficulties in proving the certainty of expesing such damages.The main achievement and conclusion of this research shows that despite apparent obstacles and traditional doubts, by citing fundamental jurisprudential and legal rules such as the "no harm" rule, the principle of the necessity of full compensation for damages, the rule of attribution, and also paying attention tion in this regard is to establish the "certainty and certainty" as well as the "directness" of the causal relationship between the breach of promise and the loss of benefits; in such a way that a clear boundary must be drawn between the mere possible benefits and the benefits of the beneficiary. The article concludes that the assessment of these damages should not be based on speculation; rather, courts can calculate the exact amount of benefits that the obligor would have definitely obtained if the obligation had been fulfilled by using specific and objective criteria, the specific conditions of each contract, and referring the matter to expert opinion. Adopting this dynamic approach, in addition to complying with reciprocity and judicial fairness, will contribute significantly to strengthening economic security and strengthening contractual relations.