How can I find out who my domain registrar is?
If you don't remember who you bought your domain from, you may be able to tell who your domain registrar is from the public domain record. You can look up your domain record through the ICANN WHOIS lookup which searches the WHOIS database.
More tips about domain registration if you aren't sure who your domain registrar is:
Your domain registrar may be the same or different from your web host. It's possible to buy these services from the same company, but they are actually different services. So you may want to check with your website host to see if they can help you figure out the company you bought your domain from, or if they are your registrar as well as your DNS hosting provider or domain host.
If you are not sure who your web host is, you can find that out by examining your DNS record, specifically your nameservers. Our favorite tool for this is LeafDNS. If your nameservers are, for example, "ns1.bluehost.com", then Bluehost is your web host.
Domain names can be difficult or impossible to get back if you lose them, so you want to make very sure to renew it with your current registrar before it expires. Expired domain names are often snapped up by companies who just sit on them until someone is willing to pay a hefty price to get them back.
And while you are at it, you may want to add domain privacy if your registrar offers it. This prevents you from getting spam from your public WHOIS data listing your administrative contact and other personal details.
You cannot transfer a domain name to a new registrar if it is close to expiry. Your WHOIS record will let you know how long your domain is renewed for. You also cannot complete a domain transfer without unlocking your domain and getting an authorization code from the current registrar, so you still need access to your old registrar to renew, transfer, or do anything else with your domain.