Microsoft Defender for Office 365 vs Mimecast

Name: Mimecast
Brand: Mimecast
Rating: 1.6 (23 reviews)

Email Security pricing comparison · 2026

Microsoft Defender for Office 365 costs $2–$5/user/mo, while Mimecast is quote-based.

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2 products · Email Security

Side-by-side · live

Microsoft Defender for Office 365

Microsoft Defender for Office 365 (formerly Office 365 Advanced Threat Protection) is an i

verified 5d ago

$250 $32K

View pricing →

Mimecast

Mimecast is a comprehensive email security platform offering protection against phishing,

verified 4mo ago

$250 $32K

View pricing →

Recorded annual contract medians

Microsoft median is $32K less than Mimecast · different customer contracts; not a quote

Cheapest $250

Spread 99%

Estimated license cost

at 25 seats

List price × seats. Click a tier below to lock it.

Microsoft Defender for Office 365 (Plan 2)

$1.5K/yr

year 1 license · $5/seat

Pricing model unknown

no public list price found

What buyers actually pay

median, annual

Vendr deal-flow data. The real benchmark, not list price.

↓ Lowest median

Median annual

$250/yr

Vendr · n=42

Median annual

$32K/yr

Vendr · n=79 avg 12% negotiated

REF · 01

Sources & confidence

Every dollar amount and contract clause below traces back to a sourced fact. We don't manufacture composite scores.

Where this data comes from

Vendr · TrustRadius · Reddit · BBB · official docs

Sources 3 sourced facts

1 contract · Vendr median · 1 review platform

Last verified 5d ago

Confidence High confidence

Sources 11 sourced facts

5 hidden-cost · 4 contract · Vendr median · 1 review platform

Last verified 3mo ago

Confidence High confidence

REF · 02

Plans at a glance

Every tier per product. Lock one to drive the cost row above and reveal a tier-specific outbound CTA.

Tier ladder

Click a tier to lock the cost row to it. Locking surfaces a tier-specific Visit CTA.

REF · 03

Hidden costs

Each cost is severity-ranked, with the dollar range quoted from its source (Vendr, Reddit, TrustRadius, BBB, official docs) — never our estimate.

Beyond the sticker

Severity-ranked, sourced

No hidden costs documented

4 documented

Mid-Contract True-Up Charges

5-15% of license costs

1 source
Proofpoint Integration API Dependency

$3,000-$8,000

1 source
Support Tier Costs

10-20% of license costs

2 sources
Implementation and Setup Costs

$2,000-$5,000

1 source

REF · 04

Contract terms

The fine print, surfaced. Green = buyer-friendly. Each clause backed by a quoted source.

Microsoft

Mimecast

Auto-renewal

—

Yes

Cancellation

seven days after the start or renewal

90 days before renewal

Commitment

—

1 year typical

Price escalation

—

5-8% annual uplift standard at renewal. Multi-year agreements often include built-in price increases for each year. Users report 40% increases at some renewals.

Can downgrade

—

REF · 05

What users say

Aggregated, with sample sizes. We use whichever review platform has data.

User reviews

TrustRadius · Trustpilot · G2

TrustRadius

8.2out of 5 (32)

Best for

General users and teams

Watch out

Requires specific Microsoft training to implement effectively

Trustpilot

1.6out of 5 (23)

Best for

Foundational email security

Watch out

Blocks legitimate emails from trusted senders repeatedly

Decide

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Visit Microsoft pricing

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Visit Mimecast pricing

Discount programs →

License cost is computed from publicly listed plans (real math, list price × seats). Median annual cost is from Vendr's deal flow when available — see source badges. Hidden costs and contract terms each cite their own sources. We do not invent composite scores.

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