The Short Answer
Use used to for a past habit or situation in a statement: “I used to walk to school.” In questions and negatives with did, drop the d: “Did you use to walk to school?” and “I didn’t use to walk to school.” The shortcut is simple: did already marks the past.
That final d is easy to miss, especially because used to and use to can sound nearly identical in conversation. In writing, though, you can choose the form by checking the sentence rather than trusting your ear.
What “Used To” Means
Used to describes something that happened regularly in the past or was true for a period of time but is no longer true. It often sets up a contrast between then and now:
- “We used to play cards every Friday.” Perhaps Friday nights look different now.
- “This building used to be a library.” It serves another purpose today.
The pattern is used to + base verb: used to play, used to live, used to be. It works for actions and situations alike. “She used to cycle to work” describes a repeated action; “She used to live nearby” describes a past situation.
In an ordinary affirmative statement, keep the d, no matter who the subject is: “I used to,” “he used to,” and “they used to” all follow the same pattern. Don’t write “I use to live nearby” when you mean that you lived there in the past.
Why Questions Change to “Use To”
To ask about a past habit, put did before the subject and write use to without the d:
Did + subject + use to + base verb?
“Did your family use to eat dinner together?” and “Where did you use to work?” both follow that pattern. In the second question, where comes first, but did still carries the past tense.
This is the same pattern you use with many other past-tense questions. “You walked home” becomes “Did you walk home?”—not “Did you walked home?” Likewise, “You used to walk home” becomes “Did you use to walk home?” For a closer look at that helper verb, see why English questions need do, does, and did.
One useful distinction: not every sentence containing a question word follows this pattern. In “Who used to live here?” who is the subject, and there is no did. Keep used to.
Why Negatives Also Use “Use To”
The everyday negative form is didn’t use to + base verb:
“I didn’t use to like coffee, but I drink it every morning now.”
“Those buses didn’t use to stop here.”
Again, didn’t supplies the past tense, so use loses its final d. Writing “didn’t used to” is common, but didn’t use to is the safer choice for edited writing and exams. Cambridge notes that both spellings appear, while warning that many people consider the form with -d incorrect in exams.
The same principle applies to negative questions: “Didn’t you use to have a dog?” Although the question begins with didn’t, the verb still stays in its base form.
You may also encounter “She used not to eat meat.” This is a possible, more formal negative form, but it is not the one most people need for everyday writing. If you want a straightforward sentence, “She didn’t use to eat meat” will usually do the job.
A Quick Test for Any Sentence
When you hesitate between the two spellings, ask: Is there a helping did or didn’t attached to this past-habit phrase?
If the answer is yes, write use to:
- “Did they use to visit every summer?”
- “They didn’t use to visit in winter.”
If the answer is no, write used to in a straightforward statement:
- “They used to visit every summer.”
Try changing “They used to visit every summer” into a question and a negative. If you get “Did they use to visit every summer?” and “They didn’t use to visit every summer,” you have the rule.
Be careful not to turn this into “Every sentence with the word not needs use to.” The shortcut concerns did and didn’t, not every possible way to make a sentence negative.
Don’t Confuse It With “Be Used To”
There is another expression that looks similar but means something different. Be used to means be accustomed to: “I’m used to the noise.” Get used to describes becoming accustomed to something: “I’m getting used to the noise.”
Compare these sentences:
“I used to wake up early.” That was a past routine.
“I am used to waking up early.” Waking up early feels familiar to me now.
After be used to or get used to, use a noun, pronoun, or -ing verb form. The did shortcut does not apply in the same way: “Are you used to waking up early?” asks whether it feels familiar, not whether you had that habit in the past. The British Council’s guide to the different uses of used to explains that distinction with more examples.
Put the Rule to Work
Imagine you are describing an old neighborhood. Start with a statement: “There used to be a bakery on this corner.” Ask a former neighbor: “Did there use to be a bakery here?” Then describe what was absent: “There didn’t use to be so many cars.”
All three sentences refer to the past. Only the statement needs used to; the question and negative already have did. That is the choice to remember when you write: used to on its own, use to after did or didn’t.