The competitive insurance industry requires effective communication to sustain customer trust. This study examines how marketing communication dimensions influence brand loyalty at PT. BRI Asuransi Indonesia (BRINS). A quantitative survey of 400 active customers was analyzed using PLS-SEM to measure the effects of advertising, public relations, direct marketing, and sales promotion on brand loyalty. All four communication dimensions significantly increased brand loyalty, with public relations having the strongest influence. The model explained 65.3 percent of the variation in brand loyalty (R² = 0.653) and showed strong predictive relevance (Q² = 0.419). These findings emphasize the importance of integrated marketing communication strategies in building and maintaining customer loyalty in the insurance sector. Attractive and credible advertising increases awareness and positive perceptions of the brand. Public relations is a key factor because it builds trust through transparency and two-way communication, which is crucial in a trust-based industry. Personalized direct marketing strengthens emotional connections and customer retention, while sales promotions encourage repeat purchases through the perception of added value. Conceptually, these results reinforce Relationship Marketing Theory, which emphasizes the importance of continuous communication, trust, and shared value in forming long-term loyalty. Integrated marketing communication is essential for strengthening trust, relationships, and brand loyalty. The findings support Relationship Marketing Theory and suggest that insurance companies should apply credible, consistent, and customer-focused communication strategies.