On-Month-In-Month | Commonly Confused Words

On month

/ɑn mʌnθ/

Indicates time within a specific month

This word has no synonyms

This word has no antonyms

/ɪn mʌnθ/

In the specific period of approximately four weeks within a calendar year

This word has no synonyms

This word has no antonyms

Use in with months when referring to a time period within that month, like in March.
Remember that on is used with specific days, not months, such as on Tuesday.
In is used for longer periods, so think of a month as a longer span compared to a day.
If you are referencing a holiday within a month, say on before the specific holiday and use in when speaking generally about the month.
The phrase in month suggests a broader sense of time, whereas on pinpoints a specific day.