Campaign Monitor

Campaign Monitor (launched 2004) excels at email design with professionally built templates and a visual editor that outputs clean, responsive HTML. WordPress form plugins connect for list building. A/B testing compares subject lines and content variants to optimize open rates and clicks, with detailed reports on subscriber engagement.

Newsletter publishers and small agencies will value the design-forward approach and A/B testing depth. It's stronger for campaign quality and consistency than for high-volume transactional email or deep ecommerce automation, making it ideal for teams prioritizing polished campaigns over complex workflows.