The article is devoted to the theoretical conceptualization of personal financial security as a key structural and functional element of economic culture under the conditions of digitalization and transformation of the financial and behavioral environment. It is substantiated that financial security cannot be reduced to the level of income or the scope of formal knowledge, but represents a sustainable state reproduced by the internal culture of handling finances. Based on data from the Bank of Russia, NAFI and Rosstat for 2020–2025, a systemic gap has been identified between the declared importance and the actual prevalence of basic financial practices among the population of the Russian Federation, which is most pronounced in the area of long-term decisions. It has been established that the growth of household indebtedness, the scale of financial fraud and the generational gap in financial behavior represent manifestations of various deficits of economic culture and require differentiated approaches to its formation. The author's structural and functional model has been developed, revealing the interrelation between the components of economic culture, its protective, adaptive and strategic functions, and the manifestations of personal financial security. It is concluded that sustainable financial security is achievable only through the systematic formation of the value-normative core of economic culture.