Microsoft Defender for Office 365 vs Mimecast

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

Email Security pricing comparison · 2026

Microsoft Defender for Office 365 pricing ranges from $2–$5/user/month, while Mimecast uses custom pricing. Mimecast is typically 100% more affordable, though your actual cost depends on tier and team size.

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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 27d ago

$250 $32K

View pricing →

Mimecast

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

verified 23d ago

$250 $32K

View pricing →

Verdict · Vendr median · year 1

Microsoft saves $32K vs Mimecast · 25 seats

Cheapest $250

Spread 99%

Estimated license cost

at 25 seats

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

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 2 sourced facts

Vendr median · 1 review platform

Last verified 3w ago

Confidence High confidence

Sources 11 sourced facts

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

Last verified 3w 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 · 05

What users say

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

User reviews

TrustRadius · Trustpilot · G2

TrustRadius

8.2/5 (32)

Best for

General users and teams

Watch out

Requires specific Microsoft training to implement effectively

Trustpilot

1.6/5 (23)

Best for

Foundational email security

Watch out

Blocks legitimate emails from trusted senders repeatedly

Decide

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Each link opens the vendor's pricing page in a new tab.

Visit Microsoft pricing

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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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