One of the major challenges facing the banking system and capital market in Iran is their formalistic implementation, which has led to adverse economic and even cultural consequences. A key cause of this formalism is the inability of exchange-based and partnership-based contracts to address certain financial needs—such as debt repayment and working capital financing—for individuals and productive enterprises. Such financial needs are primarily linked to Qardh al-Hasanah (interest-free lending). However, since the purchasing power of the lender is not preserved in such loans, this virtuous tradition has increasingly fallen into disuse. This study, employing a descriptive-analytical method, seeks to develop an operational model through which Qardh al-Hasanah can be utilized for financing at both small and large scales, and for both short-term and long-term needs. By examining Qardh al-Hasanah and riba (usury) from jurisprudential and economic perspectives, and drawing on the legal opinions (fatwas) of leading Islamic jurists, the research concludes that it is permissible to issue Qardh al-Hasanah bonds under the condition that the purchasing power of the loan is preserved—up to the level of inflation. Similarly, in the mobilization and allocation of financial resources, the use of Qardh al-Hasanah with a condition of maintaining purchasing power can be justified within this jurisprudential framework.