Shockingly terrible customer service.

Sendgrid is a high risk partner for any serious business. Do not use this provider. Their customer service is terrible.

I raised a query to ask to upgrade my payed plan as I need to send more emails. They reply after 24 hours. I was incredibly busy and did not respond to their late email. So they found it fit to suspend my SendGrid account on the basis that I had not responded to their email. That shut down our enterprise software email sending. I had a demo with a CEO of a massive company which was blocked by this. Absolutely appalling.

I urgently and stressfully made an integration with Amazon SES. That worked like a charm and It was up and running perfectly which a much more reasonable and proper billing structure.