English UsageGrammar guide
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
Confusion Familyirregular verb inflection
Rule Familyverb forms
Termsbuy, bought
Variant ScopeThe irregular form bought serves as both simple past and past participle.
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.