An annual fee is a recurring charge billed once per year, separate from any usage-based price. In subscription services, it is the fixed cost of keeping the service active, whether or not the customer uses it heavily. In the article context, it appears as a stable yearly charge alongside a locked per-unit price.
In cyber security, annual fees are common for domains, certificates, VPNs, endpoint protection, cloud licenses, and support contracts. They matter because missed renewals can lead to expired certificates, disabled protection, or service outages. Attackers also exploit this pattern with fake renewal notices, invoice scams, and payment-page phishing that imitate legitimate subscription renewals. Defenders monitor recurring charges, renewal dates, and vendor billing to prevent both operational lapses and fraud.