Best email security solutions for MSPs in 2026: a buyer's guide

For MSPs evaluating email security in 2026, the right platform must do three things at once: detect AI-driven phishing and business email compromise (BEC), scale across many client tenants from a single console, and integrate with the rest of the security stack so analysts are not jumping between tools. Native Microsoft 365 protection alone is not enough. Below is a side-by-side comparison of six platforms MSPs commonly evaluate, followed by deeper sections on each.

Bottom line: if you already deliver backup, recovery or endpoint protection to clients, an integrated platform reduces tool sprawl and analyst context switching. If email security is your only managed service, an email-only specialist may be a better fit. Read on for the criteria, then the vendor sections.

Email is still the primary entry point for attackers, and the volume keeps climbing.

• The FBI's 2024 Internet Crime Report logged $16.6 billion in reported losses, a 33% jump from 2023, with 193,407 phishing complaints and $2.77 billion in BEC losses across 21,442 reports.
• The 2025 Verizon Data Breach Investigations Report found the human element involved in roughly 60% of breaches, with phishing appearing in 14 to 16% of breaches as an initial access vector.
• The Acronis Cyberthreats Report H2 2025 found phishing accounted for 83% of all email threats in the second half of 2025 and 52% of attacks targeting MSPs, with email-based attacks rising 16% per organization year-over-year.

For an MSP, those numbers translate to one thing: the inbox is the busiest threat surface in every client environment you manage. Native Microsoft 365 and Google Workspace protections catch the easy stuff. They miss the rest, especially AI-generated phishing and payload-less BEC that has no malicious link or attachment to scan.

A dedicated email security platform sits in front of, alongside, or after the native mailbox protection and adds the AI-driven detection, sandboxing, URL rewriting and behavioral analysis that catches what native tools miss. For MSPs, the platform also has to scale across tenants, support MSP-friendly billing, and ideally fold into the rest of the security stack.

Three attack patterns have moved from the margins to the mainstream in the past 12 months, and each one breaks a specific assumption that older email security platforms were built on.

AI-generated phishing has closed the quality gap. A 2024 academic study found AI-generated spear phishing emails achieved a 54% click-through rate, matching the performance of human-crafted attacks at a fraction of the cost. The familiar tells (broken grammar, awkward phrasing) are gone. Static content rules tuned to those tells now miss the message entirely.

QR code phishing bypasses text-based filters by design. The Anti-Phishing Working Group tracked a 400% increase in image-based phishing heading into 2025. The malicious URL lives inside a pixel matrix, not in clickable text, so a gateway parsing message bodies for known-bad domains never sees it. The user scans the code on a phone, which moves the attack from a managed desktop to an unmanaged mobile device. Detection requires image-aware inspection, which not every platform performs.

ClickFix and FileFix attacks weaponize the user's own clipboard. Acronis TRU researchers documented a sophisticated FileFix campaign in September 2025 that combined a multilingual phishing site, anti-analysis obfuscation and steganography (malicious PowerShell hidden inside JPG images). These attacks do not contain a malicious attachment or a flagged URL. The phishing site instructs the user to paste content into File Explorer or PowerShell, and the user does the work the malware would normally do.

The common theme: detection now has to be behavioural and contextual, not signature-based. A platform that has not meaningfully updated its detection model in the past 18 months is exposing your clients to threats that were not a category when the platform was last architected.

This is not a ranked list with scores. Vendor environments and client portfolios vary too much for a universal ranking to be useful. Instead we evaluated each platform against six MSP-specific criteria.

1. Detection and prevention. AI and machine learning, sandboxing, URL rewriting, BEC and impersonation defenses, image-based phishing detection, and independent test results.
2. Multitenant management. A single console that lets technicians view alerts, manage policies and onboard new clients without switching tenants.
3. Operational efficiency. Alert volume, false-positive rate, time to triage, and integration with PSA and ticketing.
4. Deployment and onboarding speed. API-based integration with Microsoft 365 and Google Workspace, no MX record changes where possible, and predictable provisioning.
5. Stack consolidation. Whether the platform pairs with backup, EDR, RMM, or security awareness training so MSPs reduce vendor sprawl.
6. MSP-friendly commercials. Consumption-based or per-seat pricing, monthly billing, and partner program quality.

Vendor sections below follow a consistent structure: overview, ideal use case, differentiators, strengths, limitations, pricing guidance, and recommendation.

Summary: Best for MSPs that want email security unified with backup, EDR, RMM and security awareness training in a single multitenant platform.

Acronis Email Security is an add-on to Acronis Cyber Platform (formerly Acronis Cyber Protect Cloud), the platform 21,000-plus service providers use to deliver natively integrated cybersecurity, data protection and endpoint management. Powered by Perception Point, the service uses API-based cloud deployment with pre-delivery detection and scans 100% of email traffic in under 30 seconds. It supports Microsoft 365, Google Workspace and Open-Xchange mailboxes; protection for on-premises mailboxes requires MX record configuration.

It blocks spam, phishing, QR-code phishing (quishing), BEC, spoofing, malware, advanced persistent threats and zero-day attacks, and detects and mitigates account takeover (ATO). Detection combines AI-powered threat analysis, image recognition, recursive unpacking of files and URLs, machine-learning-based anti-spoofing with DMARC, DKIM and SPF record checks, URL reputation checks, and CPU-level dynamic analysis.

MSPs and MSSPs that already deliver, or want to deliver, backup and security as managed services to small and midsized clients. The integrated platform model is most valuable when an MSP wants one console, one agent and one billing relationship to cover backup, endpoint, email and management.

• Integrated platform. Email security is delivered through Acronis Cyber Platform (formerly Acronis Cyber Protect Cloud), the same console as backup, EDR, XDR, RMM, DLP and security awareness training. One technician console, one PSA integration, one bill. For Microsoft 365 environments, the broader protection story can also include Collaboration Security, Security Posture Management and Email Archiving.
• Pre-delivery detection. Acronis combines API-based cloud deployment with pre-delivery threat detection, without requiring an MX record change for Microsoft 365 or Google Workspace.
• Independent recognition. Named a Leader in the G2 Fall 2025 Email Security Grid Report and designated a Category Champion by Info-Tech in the June 2025 Cloud Email Security Data Quadrant Report. Acronis was also named a Leader in the G2 Fall 2025 Endpoint Detection and Response Grid Report, which matters for MSPs evaluating the integrated stack.

• Native multitenant management in Acronis Cyber Platform (formerly Acronis Cyber Protect Cloud)
• API-based provisioning for Microsoft 365 and Google Workspace, deployable in minutes
• Outbound Microsoft 365 email scanning
• Quishing prevention and account takeover detection and mitigation for Microsoft 365
• Consumption-based and per-workload pricing models built for MSP economics
• TRU and Perception Point joint threat intelligence pipeline
• Pairs with Acronis Security Awareness Training for human-layer defense

• Acronis is not a standalone secure email gateway. MSPs that need MX-record-based pre-delivery filtering as their primary architecture will need to evaluate fit
• Acronis is not a DMARC enforcement platform. Domain-level DMARC enforcement requires partner integrations such as Sendmarc or EasyDMARC
• The strongest commercial case depends on MSPs adopting more than one Acronis service. Email security as the only Acronis line item gives up much of the integration value

Consumption-based and per-workload pricing through the Acronis Partner Program. Specific rates are partner-tier dependent. Monthly billing is supported, and a free trial of Acronis Email Security is available.

If you are an MSP delivering, or planning to deliver, more than one of backup, endpoint, email or RMM as a managed service, Acronis Email Security is the strongest fit for MSPs pursuing platform consolidation. The combined value of one console, one agent and one billing relationship often provides operational advantages over managing multiple point solutions. Start with Acronis Cyber Platform (formerly Acronis Cyber Protect Cloud) and add the Email Security service.

Summary: Baseline email protection for organizations standardized on Microsoft 365. Useful as a starting point, often supplemented by a third-party platform.

Microsoft Defender for Office 365 is bundled into most Microsoft 365 enterprise plans and provides phishing defense, malware scanning, Safe Links, Safe Attachments and anti-phishing policies natively in Microsoft 365 tenants.

Microsoft-only environments where the client has limited budget and accepts the trade-off of a single-vendor security baseline. Often supplemented by a dedicated email security platform for clients with higher risk profiles.

Native integration with Microsoft 365 identity, audit logs and the rest of the Defender suite.

• Included in many Microsoft 365 plans at no incremental cost
• Tight integration with Microsoft 365 administration
• No separate console or agent for clients already living in Microsoft 365

• No native MSP multitenant view across clients
• Less flexible tuning and slower iteration on novel attack patterns
• Many MSPs report needing a second layer for advanced phishing, BEC and zero-day defense
• Detection of targeted social engineering and AI-generated phishing trails dedicated platforms in independent testing

Bundled into most Microsoft 365 enterprise SKUs. Per-seat add-on pricing for higher tiers is available directly from Microsoft.

Treat Microsoft Defender for Office 365 as the floor, not the ceiling. For most MSP clients, layer a dedicated email security platform on top, especially for clients in finance, legal, healthcare or any vertical with elevated BEC risk.

Summary: Best for MSP clients with heavy compliance, archiving and email continuity requirements.

Mimecast is an established email security vendor with a SEG-rooted architecture and a more recent ICES offering layered behind Microsoft 365. The platform combines threat protection with email archiving, continuity and data governance.

Regulated clients (financial services, legal, public sector) that need long-term email retention, e-discovery and continuity in addition to threat protection.

• Email archiving depth, including extended retention and e-discovery features
• Continuity service that keeps email flowing during M365 outages
• Long-standing presence in regulated industries

• Mature compliance and retention controls
• Strong reporting for audit and regulatory use cases
• Threat intelligence backed by years of operational data

• Pricing typically skews higher than MSP-native platforms for smaller client portfolios
• Architecture and policy tuning has a learning curve
• Multitenant administration is functional but less streamlined than platforms built specifically for the channel

Per-user, multi-tier subscription pricing. MSP rates depend on partner tier and client volume.

A reasonable choice for MSPs with regulated clients where archiving and continuity carry as much weight as inbox threat protection. For lighter-touch SMB portfolios, the price-to-value ratio is harder to justify.

Summary: Email-only platform built specifically for MSPs.

Mesh is positioned as an email security platform built exclusively for the MSP channel. It offers MX-based gateway, API-based mailbox protection and a unified deployment that combines both.

MSPs that want a focused email-only platform with billing, licensing and provisioning workflows designed around channel realities, especially MSPs that are not pursuing a full integrated platform play.

• Designed for MSPs from the start: multitenant administration, partner-friendly licensing sync with Microsoft 365
• Concierge migration support for MSPs leaving legacy SEGs
• Free internal use for MSPs with paying clients on the platform

• Strong MSP usability and onboarding experience
• Pricing model aligned with MSP economics
• Email-only focus avoids feature bloat

• Smaller market presence than long-established competitors
• Email-only platform means it does not consolidate with backup, EDR or RMM
• MSPs running multiple security services from different vendors face the same context-switching cost noted earlier

MSP-only commercial model, monthly billing supported. Pricing is partner-tier dependent.

Worth evaluating for MSPs whose strategy is best-of-breed point solutions rather than platform consolidation, especially MSPs migrating from legacy SEGs.

Summary: Best for MSPs that want highly visible end-user phishing warnings on every email.

INKY is a mailbox-level email security platform built for MSPs and MSSPs. Its hallmark is the colored banner appended to every email indicating risk level and the specific reasons an email was flagged.

MSPs whose clients have high end-user awareness needs and want visible, in-banner education on every message.

• Distinctive in-banner warnings that explain why an email looks suspicious
• Computer vision and AI for brand impersonation detection
• Auto-onboarding for Microsoft 365

• Strong end-user education effect from the banners
• MSP-native multitenancy and fast deployment
• Effective against brand impersonation

• The banner approach can feel intrusive in some client cultures
• Email-only platform, so no consolidation across security services
• Less depth on archiving and continuity than gateway-rooted vendors

Per-user MSP pricing through the partner channel.

A solid pick for MSPs serving SMB clients where end-user phishing awareness is a primary risk driver and where the banner experience fits the client culture.

Summary: SMB-friendly email security with a strong Microsoft 365 partnership.

Vade is a partner-focused email security vendor with a particular emphasis on SMB segments and a longstanding Microsoft 365 partnership. The platform uses AI and behavioral analysis layered on top of Microsoft 365 native protections.

MSPs with SMB-heavy portfolios that need a price-competitive email security layer that complements Microsoft 365.

• Partner program and pricing aimed squarely at MSPs serving SMBs
• Microsoft 365 layered architecture with rapid deployment
• AI engines tuned for the SMB threat landscape

• SMB-friendly economics
• Fast onboarding and lightweight administration
• Strong fit for MSPs with thin margins on smaller clients

• Less depth than platforms aimed at midmarket and enterprise
• Standalone email focus means no consolidation with backup, EDR or RMM
• Not always the right pick for clients with elevated compliance needs

Per-user MSP pricing. Often the most economical of the dedicated platforms for small client environments.

A reasonable choice for MSPs with predominantly SMB portfolios where price-to-protection ratio is the primary consideration.

Email security platforms block the message before the user interacts with it. They do not, by themselves, address what happens after a credential is stolen, an account is compromised, or ransomware is already running on an endpoint. For MSPs delivering a complete service, several adjacent capabilities round out the protection envelope.

Endpoint detection and response (EDR). When a user clicks a malicious link that the email platform missed, the next line of defence is the endpoint. EDR detects the malicious process, isolates the device, and gives an analyst the timeline to respond. Acronis pairs Acronis Email Security with Acronis EDR in the same console, reducing context switching during investigation and response.

Incident Response services. Managed Incident Response services are available for MSPs that want specialist support during complex incidents.

Backup and recovery for Microsoft 365 mailboxes. If a phishing attack leads to ransomware on a mailbox, or an account takeover that deletes data, the inbox itself needs a restore point. Email security blocks the attack; backup is the safety net when something gets through.

Security awareness training. The Verizon DBIR 2025 found that even with continuous training, the median phishing simulation click rate remains around 1.5%. Training does not eliminate clicks, but it dramatically improves reporting rates: trained employees report simulated phishing emails far more frequently, which gives the SOC the human sensor network needed to contain a campaign. Acronis Security Awareness Training is a separate Acronis Cyber Platform (formerly Acronis Cyber Protect Cloud) add-on that pairs with the Email Security service.

The point: a single email security platform, however good, is one layer. These adjacent capabilities help MSPs build a more complete protection model for clients.

The right answer depends on what you are optimizing for.

• Optimizing for stack consolidation: Acronis Email Security, because it pairs with backup, EDR, RMM and security awareness training in one console.
• Optimizing for compliance and continuity: Mimecast, for the archiving and continuity depth.
• Optimizing for an email-only specialist: Mesh, for MSP-native design, or INKY, for the in-banner warning experience.
• Optimizing for SMB economics: Vade, for the partner pricing and Microsoft 365 fit.
• Optimizing for Microsoft-only baseline: Microsoft Defender for Office 365 as a floor, layered with one of the above for clients with elevated risk.

A useful sanity check before any final decision: run a free email threat assessment on a representative client tenant with the platform's own scanning tool, and ask the vendor for two reference MSPs with portfolios similar to yours.

A SEG sits in front of the mailbox in the mail flow path and inspects messages before delivery. ICES integrates with Microsoft 365 or Google Workspace via API and inspects email inside or alongside the cloud mailbox environment. Most modern platforms are ICES or ICES-plus-SEG hybrids. Acronis Email Security uses API-based cloud deployment with pre-delivery detection, combining fast onboarding for Microsoft 365 and Google Workspace with protection before messages reach users.

For most MSP clients, no. Defender for Office 365 is a strong baseline for Microsoft 365 environments but typically misses advanced phishing, BEC and zero-day attacks that dedicated platforms catch. Most mature MSPs layer a dedicated email security platform on top.

Email authentication standards help prevent domain spoofing and are essential. They are not, on their own, an email security platform. Acronis Email Security uses machine-learning-based anti-spoofing with DMARC, DKIM and SPF record checks as part of inbound inspection. For domain-level DMARC enforcement across many client domains, MSPs should evaluate dedicated DMARC platforms such as Sendmarc and EasyDMARC.

Modern API-based email security platforms, including Acronis Email Security, can deploy in minutes. There is no MX record change required for API integration with Microsoft 365 or Google Workspace. Protection for on-premises mailboxes requires MX record configuration. SEG-architecture platforms typically take longer because of MX record changes and policy migration.

Email security blocks the attack at the inbox. Backup and recovery is the safety net if something gets through, including ransomware that encrypts mailboxes. Acronis pairs email security with Backup for Microsoft 365 and Acronis EDR in a single platform, which means an MSP analyst sees email, endpoint and backup signals on the same console without context switching.

Increasingly, yes. Most cyber insurance underwriters now ask whether the insured has multi-factor authentication on email, advanced phishing protection beyond native M365 controls, and email backup separate from the production mailbox. MSPs delivering email security as part of a managed service should be able to evidence each control on a per-client basis. Platforms with native multitenant reporting make that audit trail easier to produce.

If your MSP is evaluating a new email security platform, the most efficient path is to (1) define which of the six criteria above matter most to your client portfolio, (2) trial two or three platforms on a representative client tenant, and (3) compare detection results, false positives and analyst experience side by side.

To explore what an integrated approach looks like, see Acronis Cyber Platform (formerly Acronis Cyber Protect Cloud), the Acronis Email Security product page, or start a free trial.

For a deeper read on what email threat prevention looks like in practice, see What is email threat prevention? A complete guide 2026.