Mimecast vs Startmail Comparison (2026)

Compare Mimecast vs Startmail email services. In-depth analysis of features, pricing, security, privacy, and storage to find the best email provider for your needs.

Written by

Forward Email Team

Published

4/1/26

Time to read

Less than 5 minutes

We recommend Forward Email as the best alternative to Mimecast. We also support webmail: https://mail.forwardemail.net

Email Service Comparison

20 facts in comparison

Mimecast	vs.	Startmail
Mimecast "Email & Collaboration Security" Website	vs.	Startmail "Private email you can trust" Website
See Mimecast plans (requires you to talk to a sales team) (according to a Reddit thread it may cost upwards of +$1000-2000 per month)	Pricing	$7/mo
Unknown	Storage	20 GB
200 MB	Attachments	25 MB
No	Open-Source	No
No	Sandboxed Encryption	❌ Startmail claims to use a User Vault, but this statement has not been audited and their source code is closed-source
No	Unlimited Domains	No
No	Unlimited Aliases	No
No	TTI	No
❌ Requires 3rd party	SMTP	Yes
❌ Requires 3rd party	IMAP	Yes
❌ Requires 3rd party	POP3	Yes
Yes	API	No
No	E2EE	⚠️ Supported if both sender and recipient are using OpenPGP
No	OpenPGP	⚠️ Supports OpenPGP, but does not support WKD
No	WKD	No