diff --git a/requirements-tests.txt b/requirements-tests.txt
index 5510da3c34..4094a006c8 100644
--- a/requirements-tests.txt
+++ b/requirements-tests.txt
@@ -7,7 +7,7 @@ mypy ==1.14.1; python_version < "3.9"
 mypy ==1.18.2; python_version >= "3.9"
 ruff ==0.14.8
 # For FastAPI tests
-fastapi >=0.103.2
+fastapi >=0.103.2,<0.126.0
 httpx ==0.28.1
 dirty-equals ==0.9.0
 jinja2 ==3.1.6