Overview
Before attempting to register a .CO domain, always verify availability using the EPP domain:check command. This is the most reliable, real-time method for checking registration status.
EPP domain:check (Recommended)
Submit a domain:check EPP command with the domain name. The response includes avail=1 (available) or avail=0 (not available). You can check up to 50 domain names in a single check command.
Advantages over WHOIS: real-time data, structured response, no rate limits comparable to WHOIS, reliable for automation.
WHOIS (Not Recommended for Availability Checks)
While WHOIS can indicate if a domain is registered, the .CO Registry does not guarantee the accuracy or timeliness of WHOIS data. WHOIS is subject to strict rate limits and should not be used for bulk or automated availability checking. WHOIS response formats may change without notice.
Registrar Console
For manual checks, use the Registrar Console at https://registrar-console.registry.co/. Enter the domain name to see its availability status.
Premium Status Check
Always include the Fee Extension in your domain:check to determine if an available domain is premium and what the fees are. This prevents failed transactions due to unexpected premium pricing.
Best Practice
Use domain:check immediately before submitting a domain:create command. Use the result of the create command (not a second check) to confirm registration outcome. Never use WHOIS for automated availability checking.