Graph Neural Networks (GNNs) struggle on heterophilous graphs where edges connect dissimilar nodes. Existing rewiring methods increase homophily via heuristics without theoretical guarantees, fundamentally transforming graph character. We propose LIGR (Label Informativeness-Guided Rewiring), which maximizes an information-theoretic measure quantifying how much neighbors’ labels reveal about node labels. Building on the theoretical framework of LIMO et al. (2025), we extend the binary-class threshold analysis to multi-class settings, establish provable conditions for beneficial edge modifications, and prove convergence guarantees. Experiments on 9 benchmarks across three GNN architectures (GCN, GraphSAGE, GAT) show consistent improvements, with LIGR achieving best average performance and excelling particularly on citation networks (Cora: +6.5%, CiteSeer: +5.6%, PubMed: +5.3% with GCN). LIGR preserves graph structure without explicit constraints. Ablations confirm identical homophily changes with/without constraints, showing preservation is inherent to information-theoretic optimization. LIGR induces substantially less structural change than homophily-maximizing methods (average \(|\Delta h| = 0.029\) vs. 0.071–0.080) while maintaining competitive accuracy, suitable for applications requiring interpretability (biological networks, social graphs). Code: https://github.com/smlab-niser/ligr.