N‑able Mail Assure vs Fastmail Comparison (2025)

What are the differences between N‑able Mail Assure and Fastmail?

Written by

Forward Email Team

Published

7/1/25

Time to read

Less than 5 minutes

We recommend Forward Email as the best alternative to N‑able Mail Assure.

Email Service Comparison

20 facts in comparison

N‑able Mail Assure	vs.	Fastmail
N‑able Mail Assure "Email protection to help you secure and scale" Website	vs.	Fastmail "Fast, private email that’s just for you" Website
Requires you to talk to a sales team	Pricing	$3/mo
Requires 3rd party	Storage	2 GB
Depends on inbound/outbound (e.g. 10 MB)	Attachments	70 MB
No	Open-Source	No
No	Sandboxed Encryption	No
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	No
No	OpenPGP	⚠️ Fastmail does support PGP, but not in their webmail; see this blog post for insight
No	WKD	No