SendGrid

SendGrid is Twilio's email API and deliverability platform — providing RESTful email APIs, SMTP relay service, and marketing campaign tools for businesses and developers to send transactional emails (order confirmations, password resets, notifications) and marketing emails at scale with high deliverability rates. Acquired by Twilio in 2019 for $2 billion, SendGrid processes 148 billion+ emails monthly with 80,000+ customers including Airbnb, Spotify, and Uber relying on its infrastructure for critical communication.\n\nSendGrid's platform provides two main capabilities: the Email API for programmatic transactional email sending (developers integrate the REST API or SMTP relay to trigger automated emails from their applications) and the Marketing Campaigns product for newsletter and promotional email management with a template editor, contact list management, and campaign analytics. SendGrid's deliverability infrastructure — IP warm-up management, bounce handling, unsubscribe processing, feedback loop management with major ISPs — handles the technical complexity of ensuring emails reach inboxes rather than spam folders at sending volumes where individual sender reputation management becomes critical.\n\nIn 2025, SendGrid faces the evolving deliverability landscape as Microsoft Outlook joined Gmail in implementing stricter sender requirements (DMARC authentication, unsubscribe handling, complaint rate thresholds) that senders must meet to avoid spam filtering. As part of Twilio, SendGrid is integrated into Twilio's Customer Engagement Platform alongside voice, SMS, and WhatsApp. SendGrid competes with Mailgun (Rackspace), Postmark (ActiveCampaign), Amazon SES, and SparkPost for transactional email API market share. The 2025 strategy focuses on growing as an integrated Twilio product for customers using multiple communication channels, expanding deliverability guidance tools for senders navigating tightening inbox provider requirements, and maintaining deliverability leadership.