The last company I worked for used:
Rackspace offers business-class email hosting service for small businesses. It is perfect for users who are looking for reliable email servers that can handle their email campaigns. Rackspace uses Outlook and Rackspace email service for email hosting. The prices of both services may vary.
The best thing about Rackspace is that you can use it as an add-on with your Cloudways managed hosting service. With Rackspace, you get email filtering options to keep your inbox spam and junk-free. Moreover, Rackspace guarantees that it won’t sell user data. It complies with the General Data Protection Regulation (GDPR) and California Consumer Privacy Act (CCPA). With Rackspace, you get 24/7/365 chat service, ticketing system, and in-phone support. You also get 25GB email storage with all Rackspace email plans. The basic plan starts with $2.99 per user per month.