SendGrid

SendGrid launched in 2009 out of the Techstars accelerator and grew into one of the largest transactional email senders on the internet before Twilio bought it in 2019 for roughly two billion dollars. In February 2026 Twilio folded the standalone sendgrid.com site into twilio.com, so the product now lives under the Twilio brand even though the API, dashboards, and existing integrations kept working through the move. The Email API handles the triggered mail apps send automatically, with dynamic templates, event webhooks for tracking bounces and opens, and dedicated IP options once volume justifies them.

Billing runs by email volume for the API product: a free tier allows 100 emails a day, the Essentials tier starts near $20 a month for 50,000 emails, and Pro plans scale from there with a dedicated IP included at the higher tiers. Marketing Campaigns, SendGrid's separate bulk-sending tool, bills by contact count instead and isn't included in an API plan, so a team using both ends up paying for two products. Deliverability infrastructure here is mature and well documented, which makes SendGrid a solid default for a team already inside Twilio's ecosystem for SMS or voice and wanting one vendor for email too.