Email marketing can significantly boost ROI with the right strategies. Personalization, such as using subscriber behavior and preferences, increases engagement. Optimizing send times ensures messages reach audiences when they’re most active. Crafting compelling subject lines improves open rates, while mobile-friendly designs enhance user experience and interaction. Finally, tracking performance through A/B testing and analytics allows for continuous improvement. By implementing these five hacks, businesses can maximize email marketing success and drive substantial returns on investment.