Why Built-in Spam Filters Are Not Enough
Google Workspace and Microsoft 365 include spam filtering. It catches the obvious stuff — Nigerian prince emails, Viagra ads, obvious malware attachments. It does NOT catch targeted phishing emails impersonating your CEO, fake invoice emails from "vendors you know," or credential harvesting pages hosted on legitimate services. For that, you need a dedicated email security gateway that analyzes sender reputation, link destinations, attachment behavior, and language patterns using AI.
| Product | Starting Price | AI Detection | Link Protection | Best For |
|---|---|---|---|---|
| Avanan | $3-5/user/month | ✅ Advanced AI | ✅ Time-of-click | M365/Google Workspace users |
| Proofpoint Essentials | $3-4/user/month | ✅ ML-based | ✅ URL defense | Enterprise-grade at SMB price |
| Mimecast | $3-5/user/month | ✅ Targeted threat | ✅ URL protect | Larger SMBs, compliance needs |
| Barracuda | $2.50/user/month | ✅ AI-based | ✅ Link protect | Best budget option |
| SpamTitan | $2/user/month | ✅ Basic ML | ✅ | Lowest cost, basic needs |
Detailed Reviews
1. Avanan — Best AI-Powered Detection
Avanan (acquired by Check Point) takes a unique API-based approach — it sits inside your Microsoft 365 or Google Workspace tenant via API integration, not as an SMTP gateway. Deployment takes 5 minutes with no MX record changes. Its AI engine is trained on trillions of emails and catches sophisticated attacks including business email compromise, account takeover, and credential harvesting that bypass traditional filters. At $3-5/user/month, it is priced competitively with enterprise options. Avanan is our top pick for most small businesses.
2. Proofpoint Essentials — Enterprise Tech, SMB Package
Proofpoint protects most Fortune 500 companies. Proofpoint Essentials is the same technology packaged for small business at $3-4/user/month. It includes URL defense (rewrites and scans links at click time), attachment sandboxing (detonates suspicious attachments in a virtual environment), and impostor detection (flags emails pretending to be from your CEO). If you want the most proven enterprise email security at SMB prices, Proofpoint delivers.
3. Mimecast — Best for Compliance & Archiving
Mimecast combines email security with email archiving, continuity (access email even if M365 goes down), and compliance features. For businesses in regulated industries (legal, finance, healthcare) that need email retention and e-discovery capabilities, Mimecast provides security + compliance in one platform. Pricing is higher and the feature set is broader than most small businesses need — but if you need archiving anyway, the bundle makes sense.
4. Barracuda Email Protection — Best Budget Option
At $2.50/user/month, Barracuda offers solid AI-based phishing detection, link protection, and attachment sandboxing at the lowest price among full-featured options. It lacks some of the advanced AI sophistication of Avanan and Proofpoint, but catches the vast majority of threats. A good choice if budget is the primary concern but you still want dedicated email security beyond the built-in filter.
5. SpamTitan — Lowest Cost, Basic Protection
SpamTitan is the cheapest option at ~$2/user/month. It uses dual antivirus engines (Bitdefender + ClamAV) plus basic machine learning for spam and phishing detection. It lacks the sophisticated AI-based BEC detection of Avanan and Proofpoint, but provides solid protection against known threats, spam, and malware. Best for businesses that want to add a layer of email security beyond the built-in filter at minimal cost.
Test Your Team's Phishing Detection Skills
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Take the Phishing Quiz →Our Recommendation
- 🟢 Best for most small businesses: Avanan — 5-minute setup, best AI detection, $3-5/user/month
- 🟢 Enterprise-grade at SMB price: Proofpoint Essentials — same tech Fortune 500 uses
- 🟡 Need email archiving + compliance too: Mimecast — security + continuity + archiving
- 🟢 Tightest budget: Barracuda ($2.50) or SpamTitan ($2/user/month)