In the end, I picked https://mailersend.com which looks like a fairly new service because of their generous free tier and the smoother "ramping up" price. Let's see how it goes. - Source: dev.to / over 1 year ago

- Use [notifications@customdomain.com](mailto:notifications@customdomain.com) for transactional mails (notifications) for my app. For this I will an email service (https://mailersend.com) to ensure better delivery rate as I've heard sending transactional mails with Gmail is not the best idea since it has poor delivery rate compared to these kinds of services. Source: about 2 years ago

A relative new player is MailerSend (https://mailersend.com/). We've moved all of our transactional e-mail over to their service. They have a sensible onboarding and UI/dashboard. There is a generous free tier for a single domain. A single paid account supports multiple domains starting at $25/mo for 50k outbound. Support has been excellent. And the biggest upside is that their IP range, so far, is clean and not... - Source: Hacker News / over 2 years ago

I use Soverin: https://soverin.net/ which lets you create multiple mailboxes on the same 3.25/month package. - Source: Hacker News / about 1 year ago

I have been using https://soverin.net. It has a privacy-first approach to email, while at the same time they are transparent in regards to its operation. They operate and are based in the Netherlands. - Source: Hacker News / almost 2 years ago

Soverin and AnonAddy are worth looking into imo. Soverin supports unlimited custom domain aliases. Source: about 2 years ago

Don’t forget the guys at https://soverin.net/ as well. Decent pricing and solid NL hosting and very private. Source: about 2 years ago