# LAST\_DAY

The `LAST_DAY()` function finds the month of the input date, and then returns a date object containing the last day of that month.

## Syntax

```
LAST_DAY (dateobj)

```

## Arguments

* `dateobj`: A valid date, datetime, or parsable date string.

## Return Type

Date object. If `dateobj` is not a valid date, returns `NULL`.

## Examples

```sql
SELECT LAST_DAY('2019-01-01 05:06');

```

```output

+------------------------------+
| LAST_DAY('2019-01-01 05:06') |
+------------------------------+
| 2019-01-31                   |
+------------------------------+

```

**Related Topics**

* [Data Types](https://docs.singlestore.com/db/v9.1/reference/sql-reference/data-types.md)

***

Modified at: June 26, 2026

Source: [/db/v9.1/reference/sql-reference/date-and-time-functions/last-day/](https://docs.singlestore.com/db/v9.1/reference/sql-reference/date-and-time-functions/last-day/)

(An index of the documentation is available at /llms.txt)