The ad network that pays the most on CPM for native ads depends on several factors such as your website's niche, audience, and traffic volume. Some of the top-paying networks include Taboola, Outbrain, and Revcontent. These networks specialize in native advertising and offer competitive CPM rates. Taboola and Outbrain are known for their high-quality content recommendations. Revcontent often provides higher CPM rates for publishers with premium content. You should experiment with multiple networks to find the best one that works for your audience. Consider testing different networks to optimize revenue.