Raise your hand if you’ve had the who vs. whom argument. Isn’t it time to put that struggle to rest? Whoever is a pronoun that describes someone who performs an action, while whomever is a pronoun that describes someone who receives an action. Both whoever and whomever are interrogative pronouns that deal with people.
Whoever is a subjective pronoun: It describes an unknown person who performs an action. Take this example from Creating the National Pastime: Baseball Transforms Itself by G. Edward White: “Whoever wants to know the heart and mind of America had better learn baseball.” Here, the pronoun performs the action wants, so whoever is the correct choice.
The pronoun whomever is the objective case of whoever. This means whomever can only be used either with a preposition (e.g. to, for, or about) or with a verb (an action word) that requires a direct object. Take, for example, “She plays her guitar for whomever.” The use of the preposition for indicates that whomever is necessary here.
When to Use Whoever or Whomever
Whoever and whomever follow the he or him rule that also works with who and whom. This trick relies on the fact that him, whom, and whomever are all spelled with an M. If you can rephrase the sentence or respond to the question with him, you should use whom or whomever. You should use who or whoever if the sentence requires he.
Here’s the example again: “She plays her guitar for whomever.” Because you could also correctly say “She plays her guitar for him,” whomever is the appropriate pronoun for this sentence.
Whoever and whomever are both pronouns that deal with an unknown person. Whoever answers the question who did this? Whomever answers the question to whom was this done? To figure out which pronoun is correct, rephrase the question to ask who performs or receives the action.