diff --git a/django/contrib/gis/db/models/aggregates.py b/django/contrib/gis/db/models/aggregates.py
index 7ba2e756e7..abff1a5206 100644
--- a/django/contrib/gis/db/models/aggregates.py
+++ b/django/contrib/gis/db/models/aggregates.py
@@ -34,17 +34,14 @@ class GeoAggregate(Aggregate):
             tolerance = self.extra.get("tolerance") or getattr(self, "tolerance", 0.05)
             clone = self.copy()
             source_expressions = self.get_source_expressions()
-            if self.filter:
-                source_expressions.pop()
+            source_expressions.pop()  # Don't wrap filters with SDOAGGRTYPE().
             spatial_type_expr = Func(
                 *source_expressions,
                 Value(tolerance),
                 function="SDOAGGRTYPE",
                 output_field=self.output_field,
             )
-            source_expressions = [spatial_type_expr]
-            if self.filter:
-                source_expressions.append(self.filter)
+            source_expressions = [spatial_type_expr, self.filter]
             clone.set_source_expressions(source_expressions)
             return clone.as_sql(compiler, connection, **extra_context)
         return self.as_sql(compiler, connection, **extra_context)