Business email compromise used to be easy to spot. The grammar was off, the sender domain looked strange and the request made little sense. AI-written phishing has removed most of those tells. Attackers can now write a convincing invoice reminder in a vendor’s tone, reply inside a hijacked thread and translate the same lure into a dozen languages in minutes. The result is that the messages most likely to cost a company money often carry no malicious link or attachment at all, only a plausible request to change bank details or pay a new supplier.
That shift is why email security buying has moved away from pure gateway filtering and toward tools that model normal behavior: who usually writes to whom, how a given vendor phrases a payment request and when an account suddenly starts acting differently. Most of the products below connect to Microsoft 365 or Google Workspace through an API, some still offer gateway deployment, and several combine both. If you are still mapping the basics, our guide to enterprise email security for growing businesses covers the foundations before you compare vendors.
We selected the ten companies below for their focus on BEC, impersonation and account takeover, and for how clearly each one explains its detection approach. Every entry is ranked on merit, and no company paid for placement.
Email Security And BEC Prevention Companies At A Glance
Company
Headquarters
Best For
Core Services
Abnormal AI
San Francisco, USA
Microsoft 365 and Google Workspace teams replacing a gateway
Behavioral AI email security, account takeover protection, AI phishing coaching
Inline and API email security, BEC detection, link and QR code analysis
Barracuda
Campbell, USA
Small and mid-sized businesses wanting one bundled suite
Email protection, account takeover detection, DMARC, backup and archiving
Best Email Security And BEC Prevention Companies For 2027
1. Abnormal AI — Behavioral AI Email Security Deployed By API With No MX Changes
Abnormal AI, founded in 2018 and based in San Francisco, built its product around one idea: learn how each person and vendor normally communicates, then flag messages that break the pattern. That approach suits BEC well, because an AI-written payment request from a spoofed or compromised supplier often looks clean to a signature engine but odd to a model that knows the real supplier’s habits. The company offers Inbound Email Security, Account Takeover Protection, an AI Security Mailbox for user-reported messages and an AI Phishing Coach that turns real attacks into training moments.
What stands out is the deployment model. Abnormal connects to Microsoft 365 or Google Workspace through an API and says it requires no MX record changes, which makes it a practical option for teams that want to run it alongside, or eventually replace, a secure email gateway. It has also extended into identity and AI agent security, so buyers who want email and account takeover signals in one place should put it on their shortlist. It is best for mid-sized and large organizations on cloud email.
2. Proofpoint — Core Email Protection With Supplier Threat Investigation
Proofpoint, headquartered in Sunnyvale, California, and owned by Thoma Bravo, is one of the longest-running names in enterprise email security. Its Core Email Protection product uses behavioral AI to stop phishing, BEC and evasive attacks, and can be deployed either through an API or as a secure email gateway. Around it sit Email Fraud Defense for lookalike domains and DMARC work, Account Takeover Protection, Adaptive Email DLP for misdirected messages and ZenGuide for awareness training.
The detail that matters most for BEC is Proofpoint’s Threat Protection Workbench, which pulls inbound, internal, account and supplier threats into one investigation view. Vendor email compromise is often the most expensive version of BEC, so being able to see a supplier’s compromised account and the related messages together saves analysts real time. Proofpoint also offers the Satori Abuse Mailbox Agent to automate handling of user-reported emails. It is best for large enterprises with complex mail routing, compliance requirements and a security team that will use the depth of the platform.
3. Mimecast — Gateway Or API Email Security With Social Graph Anomaly Detection
Mimecast, founded in 2003 and headquartered in London with a North American base in Lexington, Massachusetts, is a strong choice for buyers who want to pick their deployment model. Its MX-based gateway routes mail through Mimecast first so threats are blocked inline, works with any email platform and includes continuity if the primary server fails. Its API-based option connects to cloud email with no MX changes and adds AI detection on top of native protections.
For BEC, Mimecast uses social graphing to spot unusual communication patterns that may signal social engineering, along with contextual banners that warn users in real time about risky messages and QR code phishing. Computer vision checks for branding and login-page impersonation. Mimecast also sells DMARC management, archiving, security awareness training and a managed service where analysts review user-reported emails around the clock. It fits organizations with hybrid or on-premises mail, regulated archiving needs or a preference for one vendor across email, data and training.
Check Point, headquartered in Tel Aviv, acquired the cloud email security company Avanan in 2021 and now sells that technology as Harmony Email & Collaboration. It covers Microsoft 365 and Google Workspace mail, plus Microsoft Teams, SharePoint, OneDrive, Slack and file-sharing services such as Dropbox and Box. Deployment is through an API with no MX changes, and enforcement can range from monitor-only to inline prevention.
The key difference from many API-only tools is that Check Point inspects messages before they reach the inbox rather than pulling them out after delivery. That matters for BEC, where a single read of a fraudulent request can be enough. Its detection draws on Check Point’s ThreatCloud AI engines, behavioral analysis and language understanding. Add-ons include DMARC management, security awareness training, leaked credential monitoring and incident response as a service. It also aims to block poisoned content and hidden instructions aimed at AI assistants that read email. It suits companies already using Check Point or those that want collaboration app coverage in the same console.
5. IRONSCALES — Mailbox-Level Phishing Detection Built For MSPs
IRONSCALES was founded in Israel in 2014 and has run its headquarters from Atlanta since 2017, with a second base in Tel Aviv. Its platform connects to Microsoft 365 and Google Workspace by API, analyzes each mailbox’s behavior and removes every copy of a confirmed threat across the organization once it is found. Its solutions pages name BEC, vendor email compromise and VIP impersonation directly, and the company added natural language processing to detect BEC language and act on compromised accounts.
Two things set IRONSCALES apart. First, it serves managed service providers directly and through a partner network it puts at more than 3,500 MSPs, so smaller businesses often reach it through their IT provider. Second, it launched Deepfake Attack Protection for Microsoft Teams, which uses behavioral and biometric checks to catch impersonation on video calls, an attack path that sits right next to email-based BEC. It is best for MSPs, MSSPs and mid-market IT teams that want automated remediation without a large security staff.
6. Sublime Security — Agentic Email Security With Customer-Written Detections
Sublime Security, based in Washington, DC, takes a different stance from most email vendors: it shows its work. Every verdict comes with the reasoning, the detections it matched and the signals behind it. The platform targets phishing, BEC, invoice fraud and executive impersonation across Microsoft 365 and Google Workspace, and it also includes email DLP, phishing simulations, abuse mailbox automation and behavioral threat hunting.
The standout feature is control. Sublime started with a domain-specific language that lets security teams write, run and share their own detection rules, and it now pairs that with AI agents. Its Autonomous Security Analyst triages user-reported emails, while its Autonomous Detection Engineer drafts and backtests new detections specific to your environment for one-click approval. For a team that has watched a BEC lure slip through and then waited weeks for a vendor fix, writing coverage the same day is a real advantage. It is best for security teams with detection engineering skills, or those who want them, and who value transparency over a black box.
7. Material Security — Message-Level Access Controls That Limit Account Takeover Damage
Material Security, headquartered in San Francisco, protects Google Workspace and Microsoft 365 with inbound phishing and social engineering detection, plus automated triage of user-reported emails. Where it differs is in assuming that some account will eventually be compromised and planning for what happens next.
Material can redact sensitive messages sitting in a mailbox and put message-level access controls in front of them, so an attacker holding stolen credentials cannot simply search old mail for password reset links, payment details or contracts. Investigators also get a real-time view of what an attacker accessed. That post-compromise focus is relevant to BEC, because many fraud cases begin with an attacker quietly reading a finance user’s inbox to learn how payments are approved. For Google Workspace customers, Material also finds overshared sensitive files in Google Drive, such as documents containing PHI or PII, and remediates them in bulk. It is best for companies on cloud email that want to reduce the blast radius of a compromised account, not just block inbound threats.
8. Darktrace — Self-Learning Email Security Tied To Identity Response
Darktrace, headquartered in Cambridge, UK, and acquired by Thoma Bravo in 2024, applies the same self-learning approach it uses for networks to email. Darktrace / EMAIL learns from your own organization’s communication rather than a shared cross-customer model, and it needs no signatures. It targets phishing, BEC, executive impersonation and AI-generated attacks, and explains its decisions so analysts can tune it.
The connection to identity is what makes Darktrace worth a look for BEC prevention. Its Identity Detect and Respond capability can end sessions, force re-authentication and restrict access across email, SaaS and cloud when credentials appear compromised, then help audit what was accessed. Darktrace also extends behavioral detection to Microsoft Teams, Zoom and Slack, though the company notes this coverage alerts rather than blocks. An adaptive training feature adjusts each employee’s email controls based on their risk score. It is best for organizations already running Darktrace elsewhere, where shared behavioral context across email, network and identity adds the most value.
Cloudflare, headquartered in San Francisco, entered email security when it acquired Area 1 Security in 2022. Its Email Security product protects inboxes from phishing, BEC, malware and ransomware, and can be deployed inline, through an API or both. The combined mode gives pre-delivery processing, real-time link analysis and post-delivery retraction of messages that turn malicious later.
For BEC, Cloudflare analyzes each email across hundreds of attributes, including sender reputation, message sentiment and conversation context, to catch messages that impersonate employees and vendors in order to steal data or redirect payments. It also inspects malicious links and QR codes, and extends coverage to messaging and collaboration apps such as Slack and Teams. The biggest reason to choose it is consolidation: companies already using Cloudflare for zero trust access, DNS or web security can add email protection under the same vendor and console. It is best for Cloudflare customers and for teams that want flexibility between inline and API deployment.
Barracuda Networks, headquartered in Campbell, California, and owned by KKR, packages email security for organizations that want one subscription to cover most of the problem. Barracuda Email Protection connects to Microsoft 365 or Google Workspace by API with no MX changes and covers spam, malware and advanced threats, automated remediation and bulk actions, plus integrated archiving and backup.
The parts that matter for BEC are its Behavioral Account Takeover Detection, which flags compromised accounts from behavior signals rather than only login anomalies and can disable those accounts in near real time, and its domain fraud protection through DMARC. It also bundles security awareness training with phishing simulations based on current threat intelligence, and an explainable AI assistant called Bailey. Barracuda offers a free email threat scan, which is a low-effort way to see what your current setup is missing. It is best for small and mid-sized businesses, and the MSPs that serve them, that want a single vendor for protection, recovery and training.
How To Choose An Email Security And BEC Prevention Company
Most of these products will catch commodity phishing. The differences show up on the hard cases: a well-written payment request from a real vendor account, or an attacker who has been reading a finance mailbox for a week. These questions help separate the options.
Do We Need A Gateway, An API Tool Or Both?
API tools are quicker to deploy and see internal mail, which gateways often miss. Gateways block before delivery and work with on-premises or hybrid mail. If you are fully on Microsoft 365 or Google Workspace, an API product layered on native protection is often enough. If you have hybrid mail, archiving obligations or need continuity, look at vendors that offer both modes, such as Mimecast, Proofpoint or Cloudflare.
How Does It Handle Vendor Email Compromise?
Ask each vendor to show how it detects a compromised supplier account, not just a spoofed domain. Look for products that track vendor relationships over time, flag changes in banking details or tone, and give analysts a single view of all messages from a supplier that may be compromised. This is where AI-written lures do the most damage, because the sender is genuine.
What Happens After An Account Is Taken Over?
Prevention fails eventually, so check the response side. Can the tool revoke sessions, force re-authentication or disable the account automatically? Can it show what the attacker read? Products such as Material Security, Darktrace and Abnormal AI put real effort into this stage. Your incident response provider should also know how to work with whatever you choose.
How Much Work Will User-Reported Emails Create?
Good awareness programs increase reporting, and every report needs triage. Several vendors now automate abuse mailbox handling with AI agents. Ask what share of reports the tool closes without an analyst, and how it explains those decisions, before you assume your team can absorb the volume.
Can We Test Our People As Well As Our Filters?
Technology is only half of BEC defense. The other half is whether a finance clerk calls the vendor back before changing bank details. A social engineering penetration test shows how your staff and payment processes hold up against a realistic pretext, which is a useful check on any email security investment.
Conclusion
BEC is a fraud problem delivered through email, and AI-powered attacks have made the lures much harder for people and filters to catch. The strongest email security and BEC prevention companies combine behavioral detection, vendor relationship awareness and fast account takeover response. Start with your mail platform and deployment preference, shortlist two or three vendors from this list, and run each one against your own recent near misses before you sign.
