What Is Their Main Difference? Both refer to enrolling in a particular course, workshop, class, etc. However, 'sign up' is a phrasal verb, while, 'sign-up' can function as both a noun and an adjective. Differences 'Sign up' is a phrasal verb, whereas, 'sign-up' can function as both a noun and an adjective. Look at the examples below: If you wanna join Instagram, you have sign up and create an account first. You can get the sign-up paper from the office below. Similarities Both refer to registering for a specific class, workshop, etc. Look at the examples below: For more information on the sign-up process, check out the link below. Jacob signed up in the literary workshop as soon as she came into the university. Are They Interchangeable? 'Sign-up' is a noun and an adjective, while, 'sign up' is a phrasal verb. So, they cannot be used interchangeably. Compare: ✓ It seems that I cannot sign up anymore. X It seems that I cannot sign-up anymore.
