Q: The following sentence sounds fine when spoken, but too colloquial in writing: “We are planning on going to the movies tonight.” Shouldn’t one write: “are planning to” or better yet “plan to”? I generally change “are planning to” to “plan to,” much to the consternation of an ex-boss I used to edit.
A: Both “plan on” and “plan to” (as well as the progressive-tense versions you mention) are standard English, though “plan on” is more common in the US than in the UK.
But you’re right that “plan on” sounds more at home in speech or informal writing, while “plan to” seems a better choice for formal writing.
In fact, Merriam-Webster’s Dictionary of English Usage says, “Our evidence suggests that plan on is more often found in spoken than in written use; we have few printed examples.”
The only written example cited in the usage guide is from a December 1977 issue of Cats Magazine: “I will be discharged from the service in 1979 and plan on returning to the States.”
The verbal phrase “plan on” is usually followed by a gerund (“Do you plan on seeing King Lear?”), but it’s sometimes seen with a noun object (“Let’s plan on vichyssoise for lunch”).
The phrase “plan to” is always followed by an infinitive (“So when do you plan to clean your room?”).
By the way, the book Words Into Type (3rd ed.), familiar to journalists, has a handy section called “The Right Preposition,” consisting of a long list of words together with the prepositions they usually take. (It recommends that “plan” be used with “to.”)
As for “plan to” versus “are planning to,” we find the present-progressive version a bit informal, but we don’t think it would be out of place in a casual business letter.
We hope that ex-boss of yours isn’t an ex because of his consternation over your editing. If you’re planning to do that again with your next boss, maybe you should take Paul Simon’s advice and make a new plan.
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