This is the most direct way to ask someone if they are single in Spanish. It is important to note that the Spanish word for single is "soltero" for men and "soltera" for women. So, you will need to use the correct form of the word based on the gender of the person you are asking.
¿Tienes novia/novio?
This is another way to ask someone if they are single in Spanish. It is a bit less direct than asking directly if they are single, but it can be a good way to start a conversation about relationships.
¿Estás en una relación?
This is a more formal way to ask someone if they are single in Spanish. It is a good option if you are talking to someone in a professional setting or if you want to be more respectful.
¿Eres soltera/soltero?
This is a more informal way to ask someone if they are single in Spanish. It is a good option if you are talking to a friend or someone you know well.