diff --git a/src/postgrest/src/postgrest/base_request_builder.py b/src/postgrest/src/postgrest/base_request_builder.py
index fcbad9ad..2f3d272f 100644
--- a/src/postgrest/src/postgrest/base_request_builder.py
+++ b/src/postgrest/src/postgrest/base_request_builder.py
@@ -433,7 +433,11 @@ def or_(self: Self, filters: str, reference_table: Optional[str] = None) -> Self
             filters: The filters to use, following PostgREST syntax
             reference_table: Set this to filter on referenced tables instead of the parent table
         """
-        key = f"{sanitize_param(reference_table)}.or" if reference_table else "or"
+        if self.negate_next:
+            self.negate_next = False
+            key = f"{sanitize_param(reference_table)}.not.or" if reference_table else "not.or"
+        else:
+            key = f"{sanitize_param(reference_table)}.or" if reference_table else "or"
         self.request.params = self.request.params.add(key, f"({filters})")
         return self
 
diff --git a/src/postgrest/tests/_async/test_filter_request_builder.py b/src/postgrest/tests/_async/test_filter_request_builder.py
index f6e6fecd..b9bf4288 100644
--- a/src/postgrest/tests/_async/test_filter_request_builder.py
+++ b/src/postgrest/tests/_async/test_filter_request_builder.py
@@ -294,6 +294,16 @@ def test_or_(filter_request_builder):
     assert str(builder.request.params) == "or=%28x.eq.1%29"
 
 
+def test_not_or_(filter_request_builder):
+    builder = filter_request_builder.not_.or_("x.eq.1")
+
+    assert str(builder.request.params) == "not.or=%28x.eq.1%29"
+    assert not builder.negate_next
+
+    foreign = filter_request_builder.not_.or_("x.eq.1", reference_table="cities")
+    assert str(foreign.request.params) == "not.or=%28x.eq.1%29&cities.not.or=%28x.eq.1%29"
+
+
 def test_or_in_contain(filter_request_builder):
     builder = filter_request_builder.or_("id.in.(5,6,7), arraycol.cs.{'a','b'}")
 
diff --git a/src/postgrest/tests/_sync/test_filter_request_builder.py b/src/postgrest/tests/_sync/test_filter_request_builder.py
index 11cc9959..b45ce555 100644
--- a/src/postgrest/tests/_sync/test_filter_request_builder.py
+++ b/src/postgrest/tests/_sync/test_filter_request_builder.py
@@ -294,6 +294,16 @@ def test_or_(filter_request_builder):
     assert str(builder.request.params) == "or=%28x.eq.1%29"
 
 
+def test_not_or_(filter_request_builder):
+    builder = filter_request_builder.not_.or_("x.eq.1")
+
+    assert str(builder.request.params) == "not.or=%28x.eq.1%29"
+    assert not builder.negate_next
+
+    foreign = filter_request_builder.not_.or_("x.eq.1", reference_table="cities")
+    assert str(foreign.request.params) == "not.or=%28x.eq.1%29&cities.not.or=%28x.eq.1%29"
+
+
 def test_or_in_contain(filter_request_builder):
     builder = filter_request_builder.or_("id.in.(5,6,7), arraycol.cs.{'a','b'}")