diff --git a/src/firebolt/common/statement_formatter.py b/src/firebolt/common/statement_formatter.py
index d35da723dbe..91364f23867 100644
--- a/src/firebolt/common/statement_formatter.py
+++ b/src/firebolt/common/statement_formatter.py
@@ -75,7 +75,9 @@ def format_value(self, value: ParameterType) -> str:
         elif isinstance(value, datetime):
             if value.tzinfo is not None:
                 value = value.astimezone(timezone.utc)
-            return f"'{value.strftime('%Y-%m-%d %H:%M:%S')}'"
+            # Keep fractional seconds; whole-second values render as before.
+            fmt = "%Y-%m-%d %H:%M:%S.%f" if value.microsecond else "%Y-%m-%d %H:%M:%S"
+            return f"'{value.strftime(fmt)}'"
         elif isinstance(value, date):
             return f"'{value.isoformat()}'"
         elif isinstance(value, bytes):
diff --git a/tests/unit/common/test_typing_format.py b/tests/unit/common/test_typing_format.py
index ea7273d1c83..3f3586f9c97 100644
--- a/tests/unit/common/test_typing_format.py
+++ b/tests/unit/common/test_typing_format.py
@@ -52,6 +52,11 @@ def formatter_v1() -> StatementFormatter:
             datetime(2022, 1, 10, 1, 1, 1, tzinfo=timezone(timedelta(hours=1))),
             "'2022-01-10 00:01:01'",
         ),
+        (datetime(2022, 1, 10, 1, 1, 1, 123456), "'2022-01-10 01:01:01.123456'"),
+        (
+            datetime(2022, 1, 10, 1, 1, 1, 50, tzinfo=timezone(timedelta(hours=1))),
+            "'2022-01-10 00:01:01.000050'",
+        ),
         # List, tuple
         ([], "[]"),
         ([1, 2, 3], "[1, 2, 3]"),
@@ -66,6 +71,17 @@ def test_format_value(formatter: StatementFormatter, value: str, result: str) ->
     assert formatter.format_value(value) == result, "Invalid format_value result"
 
 
+def test_format_statement_keeps_datetime_fractional_seconds(
+    formatter: StatementFormatter,
+) -> None:
+    """Truncating to whole seconds silently changes stored and compared values."""
+    statement = parse("SELECT * FROM t WHERE ts = ?")[0]
+    assert (
+        formatter.format_statement(statement, [datetime(2024, 2, 29, 1, 2, 3, 4)])
+        == "SELECT * FROM t WHERE ts = '2024-02-29 01:02:03.000004'"
+    )
+
+
 @mark.parametrize(
     "value,result",
     [  # Strings
@@ -89,6 +105,11 @@ def test_format_value(formatter: StatementFormatter, value: str, result: str) ->
             datetime(2022, 1, 10, 1, 1, 1, tzinfo=timezone(timedelta(hours=1))),
             "'2022-01-10 00:01:01'",
         ),
+        (datetime(2022, 1, 10, 1, 1, 1, 123456), "'2022-01-10 01:01:01.123456'"),
+        (
+            datetime(2022, 1, 10, 1, 1, 1, 50, tzinfo=timezone(timedelta(hours=1))),
+            "'2022-01-10 00:01:01.000050'",
+        ),
         # List, tuple
         ([], "[]"),
         ([1, 2, 3], "[1, 2, 3]"),