LemList and SendGrid are both mass email platforms, but each one offers a unique set of features and services. LemList is primarily used for outbound email marketing. It has features such as contact list building, automated email series and A/B testing. It also offers advanced features for tracking performance and nurturing leads. SendGrid is more geared towards transactional emails and offers built-in email deliverability. It has features such as real-time analytics and email templates. SendGrid is a scaled email service provider that is suitable for businesses of all sizes that need fast and reliable email delivery. LemList is ideal for startups or small businesses who want to manage and automatically launch quick campaigns.