About Duo Security
Duo Security, a Cisco company, is a cloud-based cybersecurity provider specializing in multi-factor authentication (MFA), single sign-on (SSO), device trust, and secure remote access. Delivered as software-as-a-service, Duo helps organizations verify user identities and the health of devices before granting access to corporate applications and networks. Headquartered in Ann Arbor, Michigan, Duo is widely used by businesses, universities, healthcare providers, and government agencies to protect VPNs, cloud apps (like Microsoft 365, Google Workspace, and Salesforce), and internal systems.
A Duo Security charge on your bank or card statement usually relates to a subscription for Duo’s security services, often billed per user ("seat") and per month or year. Charges may appear under descriptors such as “DUO SECURITY,” “CISCO DUO,” or “CISCO DUO SECURITY SAAS.” Most customers are billed on a recurring basis—monthly or, more commonly, annually—for plans like Duo Essentials, Advantage, or Premier, which are typically priced on a per‑user basis with minimum user counts. You may also see charges after a free trial converts to a paid plan, for adding additional users or features mid-term, or for a one-time invoice paid by card instead of by check or wire. In some cases, you might see a small temporary authorization when first adding or updating a payment method.
If you’re unsure why you were charged, start by checking whether your organization uses Duo for MFA (for example, Duo Push, SMS codes, or phone callbacks when logging in). Log in to your Duo admin panel (if you are an account owner) and review the Billing or Subscription section for your current plan, billing dates, and invoices; these invoices will exactly match the amounts and dates on your statement. If you still have questions, use the support and billing contacts listed on your invoice or in the Duo admin console, or visit duo.com/support to access help resources and submit a ticket. For potential errors—such as duplicate billing, incorrect user counts, or an unwanted renewal—collect your statement details, any invoices, and your Duo account information before contacting their billing team to request clarification, adjustments, or, where applicable, a refund or credit.