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DuoCircle is a comprehensive email deliverability and security company that provides a suite of services including anti-phishing, outbound SMTP, email backup, and tenant migration
DuoCircle is a comprehensive email deliverability and security company that provides a suite of services including anti-phishing, outbound SMTP, email backup, and tenant migration. They are a remote-first organization headquartered in California, serving over 25,000 businesses worldwide by ensuring secure, reliable, and compliant email communication.
DuoCircle provides cloud-based email security and deliverability solutions that protect businesses from phishing, spam, malware, and email-based threats while ensuring outbound emails reliably reach their recipients. Their Advanced Threat Defense Suite offers real-time link click protection, phishing defense, DMARC/DKIM/SPF management, and email archiving and continuity tools. DuoCircle also supports organizations with email monitoring, deliverability analysis, and tenant migration services. Whether protecting end-users from clicking malicious links or ensuring outbound email reaches the inbox, DuoCircle handles the full email security and deliverability lifecycle.
Small and Medium Businesses (SMBs)
Growing companies that need enterprise-grade email security without the complexity or cost of building it in-house.
IT Administrators and Security Teams
Technical professionals responsible for securing organizational email environments and maintaining deliverability standards.
Managed Service Providers (MSPs) and Value-Added Resellers (VARs)
Technology partners who need a reliable, white-label-friendly email security solution they can offer to their client base.
Enterprise and Multi-Location Organizations
Larger organizations managing complex email environments across multiple departments, domains, or geographies.
DuoCircle offers a highly reliable, global email infrastructure that combines sophisticated phishing protection with seamless SMTP relay services, providing small and medium businesses with enterprise-level security features at an accessible price point.
What does DuoCircle do?
DuoCircle is a cloud-based email security and deliverability company that protects businesses from phishing, spam, malware, and email-based threats while ensuring outbound emails reliably reach their recipients. Their services include real-time link click protection, phishing defense, spam filtering, DMARC/DKIM/SPF management, email archiving, backup MX, and outbound SMTP relay.
Who is DuoCircle designed for?
DuoCircle serves organizations of all sizes, from small and medium businesses to enterprise and multi-location companies. They also offer a dedicated partner program for Managed Service Providers (MSPs) and Value-Added Resellers (VARs) who want to offer email security to their own clients.
What makes DuoCircle different from other email security providers?
DuoCircle's Link Click Protection re-checks every URL at the moment it is clicked — not just when the email is delivered — against multiple URL reputation databases. This means users are protected even if a site's content changes after the email was received. Combined with a full-spectrum suite covering inbound filtering, outbound deliverability, and authentication management, DuoCircle provides comprehensive coverage in a single platform.
What products and services does DuoCircle offer?
DuoCircle's product suite includes: Advanced Threat Defense Suite (phishing and spam protection, link click protection, malware scanning), Outbound SMTP Relay, Email Archiving and Discovery, Backup MX and Email Continuity, DMARC/DKIM/SPF Management Tools, Email Monitoring and Deliverability Analysis, and Spam Filtering.
Does DuoCircle have a partner or reseller program?
Yes. DuoCircle offers a dedicated MSP Partner Program for Managed Service Providers and Value-Added Resellers, allowing technology partners to resell and deliver DuoCircle's email security services to their own clients.
How many businesses use DuoCircle?
DuoCircle is trusted by over 25,000 businesses worldwide across multiple industries.
Where is DuoCircle headquartered and how is it structured?
DuoCircle is headquartered in California, USA, and operates as a remote-first company with team members located globally.
What problem does DuoCircle solve?
DuoCircle addresses the risk of email-based cyberattacks — particularly phishing and social engineering — which, according to the 2025 Verizon Data Breach Investigation Report, are linked to human error in 60% of data breaches. DuoCircle protects end-users from clicking malicious links, keeps inboxes free of spam and malware, and ensures outbound emails reach their destination reliably.