SITE.su operates an online marketplace for premium domain names, offering a catalog of more than 40,000 domains in the .ru, .su, and .рф extensions. The service helps businesses and individuals find an address for a website, brand, or personal project, with listings searchable by keyword and related terms. Customers can browse the full inventory, use advanced search, or download a domain list with available metrics.

Domains are available for immediate purchase or monthly rental. The marketplace describes its rental option as including a guaranteed right to buy, while purchased domains are transferred online. Each listing can show pricing for both options alongside information such as domain age and ratings. For example, ulija.ru is listed for purchase or rent, with related suggestions displayed to help visitors explore alternatives. Users can contact the marketplace through its help section or online chat, ask questions about a specific domain, and propose a price. The site also provides account access for customers who want to register and manage transactions.