diff --git a/ibis/backends/mssql/registry.py b/ibis/backends/mssql/registry.py
index d0695eda9338..6d06bd2dcc58 100644
--- a/ibis/backends/mssql/registry.py
+++ b/ibis/backends/mssql/registry.py
@@ -20,8 +20,11 @@ def reduction_compiler(t, op):
         arg, where = op.args
 
         if arg.output_dtype.is_boolean():
-            nullable = arg.output_dtype.nullable
-            arg = ops.Cast(arg, dt.dtype(cast_type)(nullable=nullable))
+            if isinstance(arg, ops.TableColumn):
+                nullable = arg.output_dtype.nullable
+                arg = ops.Cast(arg, dt.dtype(cast_type)(nullable=nullable))
+            else:
+                arg = ops.Where(arg, 1, 0)
 
         if where is not None:
             arg = ops.Where(where, arg, None)
diff --git a/ibis/backends/tests/test_aggregation.py b/ibis/backends/tests/test_aggregation.py
index d93125dc0ca6..c06481e9398d 100644
--- a/ibis/backends/tests/test_aggregation.py
+++ b/ibis/backends/tests/test_aggregation.py
@@ -418,11 +418,6 @@ def mean_and_std(v):
                         "function sum requires numeric or interval types, not boolean;"
                     ),
                 ),
-                pytest.mark.notimpl(
-                    ['mssql'],
-                    raises=sa.exc.OperationalError,
-                    reason="Incorrect syntax near the keyword 'AS'",
-                ),
             ],
         ),
         param(
@@ -1429,11 +1424,6 @@ def test_filter(backend, alltypes, df):
         "function sum requires numeric or interval types, not boolean;"
     ),
 )
-@pytest.mark.notimpl(
-    ["mssql"],
-    raises=sa.exc.OperationalError,
-    reason="Incorrect syntax near the keyword 'AS'",
-)
 def test_column_summary(alltypes):
     with pytest.warns(FutureWarning, match="is deprecated"):
         bool_col_summary = alltypes.bool_col.summary()
diff --git a/ibis/backends/tests/test_window.py b/ibis/backends/tests/test_window.py
index e4285a3e273d..eb40e7d5292a 100644
--- a/ibis/backends/tests/test_window.py
+++ b/ibis/backends/tests/test_window.py
@@ -159,7 +159,6 @@ def calc_zscore(s):
                     "duckdb",
                     'impala',
                     'postgres',
-                    'mssql',
                     'mysql',
                     'sqlite',
                     'snowflake',
@@ -193,7 +192,6 @@ def calc_zscore(s):
                     "duckdb",
                     'impala',
                     'postgres',
-                    'mssql',
                     'mysql',
                     'sqlite',
                     'snowflake',