Past Tense of Buy
The simple past of “buy” is “bought,” and the past participle is also “bought.” The standard principal forms are buy, bought, bought.
Use “bought” for both the simple past and the past participle of “buy.”
Key details
Choose the right form
| Meaning / situation | Form / construction | Decision |
|---|---|---|
| completed action in the past | bought | Use “bought” as the simple past. |
| perfect construction after have/has/had | bought | Use the same form as the past participle. |
| present/base form | buy / buys | Keep the present form; do not use a past form. |
Quick tests
Meaning / construction test
Do you need either the simple past or the past participle of “buy”?
If yes: Use “bought.”
If no: Use the present/base form when the sentence is not calling for a past form.
Examples
I bought a new notebook yesterday.
“Bought” is the simple past for a completed past action.
She has bought the tickets already.
“Bought” is also the past participle after “has.”
They buy fruit here every week.
The present-tense context keeps the base form “buy.”
Further guidance
Core difference
“Buy” is irregular: its simple past and past participle are both “bought.”
Fast Test
For a completed past action, use “bought”; after have/has/had, use the same participle “bought.”
Usage Boundary
Do not form the standard past as “buyed.”
Sources and evidence
Sources are shown with the role they play in this guide. Historical or style-sensitive claims are kept within the evidence boundary described above.
- Bought — Cambridge Dictionary (opens in a new tab)Cambridge University Press · Authority used to verify the public wording and usage boundary.