Once you receive your activation code via email, you must apply it to your Nessus installation. You can activate the software online or offline. Method 1: Online Activation (Recommended)

Select and choose the Offline registration option. Copy the unique Challenge Code displayed on the screen.

If your license has fully expired beyond the allowable renewal period, it will need to be treated as a new purchase rather than a renewal. Contact Tenable sales or your authorized reseller for assistance in these situations.

Download the generated nessus.license file and the latest plugin archive.

The cost of a Nessus Professional license is a significant consideration for most organizations and individuals. Based on current market data, pricing varies by subscription term, features, and volume.

Nessus Professional annual subscriptions typically start around $2,400 to $2,990 per year (approximately 17,000–21,000 RMB), while Nessus Expert pricing begins at approximately $3,990 to $5,990 per year. These prices reflect the standard commercial rates for single-user licenses. Organizations requiring additional features like multi-user management or API access will need to consider enterprise-tier solutions, which often start at $4,200+ annually and scale based on asset count.

sudo /opt/nessus/sbin/nessuscli fetch --register <your-activation-code>

If you are evaluating the software, Tenable offers a . This allows you to test the full features of the "Pro" version on your specific network environment before committing to a purchase. 3. Nessus Essentials (The "Free" Key)

Nessus Professional is the paid version of the software, offering a wide range of advanced features and capabilities that make it an essential tool for organizations serious about cybersecurity. Some of the key benefits of Nessus Professional include: