diff --git a/pyproject.toml b/pyproject.toml
index 26f2df9..c67db70 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -7,7 +7,7 @@ dependencies = [
     "alembic~=1.14.0",
     "authlib~=1.3.0",
     "dataclass-wizard~=0.26.0",
-    "flask~=3.0.0",
+    "flask~=3.1.0",
     "flask-session[sqlalchemy]~=0.8.0",
     "govuk-frontend-jinja~=3.1.0",
     "govuk-frontend-wtf~=3.1.0",