diff --git a/Lib/test/test_json/test_float.py b/Lib/test/test_json/test_float.py
index d0c7214334d6e5..8abcf317253083 100644
--- a/Lib/test/test_json/test_float.py
+++ b/Lib/test/test_json/test_float.py
@@ -26,8 +26,9 @@ def test_allow_nan(self):
                 res = self.loads(out)
                 self.assertEqual(len(res), 1)
                 self.assertNotEqual(res[0], res[0])
-            self.assertRaises(ValueError, self.dumps, [val], allow_nan=False)
-
+            self.assertRaisesRegex(
+                ValueError, str(val), self.dumps, [val], allow_nan=False
+            )
 
 class TestPyFloat(TestFloat, PyTest): pass
 class TestCFloat(TestFloat, CTest): pass
diff --git a/Misc/NEWS.d/next/Library/2022-11-06-19-59-56.gh-issue-86018.xAt6g2.rst b/Misc/NEWS.d/next/Library/2022-11-06-19-59-56.gh-issue-86018.xAt6g2.rst
new file mode 100644
index 00000000000000..dad1fc22f47b2a
--- /dev/null
+++ b/Misc/NEWS.d/next/Library/2022-11-06-19-59-56.gh-issue-86018.xAt6g2.rst
@@ -0,0 +1 @@
++ Fix issue where the error messages for :meth:`json.dump` and :meth:`json.dumps` were inconsistent when serializing non-finite values with ``allow_nan=False``
diff --git a/Modules/_json.c b/Modules/_json.c
index fe8695110f017d..f496b9401e1baa 100644
--- a/Modules/_json.c
+++ b/Modules/_json.c
@@ -1325,9 +1325,9 @@ encoder_encode_float(PyEncoderObject *s, PyObject *obj)
     double i = PyFloat_AS_DOUBLE(obj);
     if (!Py_IS_FINITE(i)) {
         if (!s->allow_nan) {
-            PyErr_SetString(
+            PyErr_Format(
                     PyExc_ValueError,
-                    "Out of range float values are not JSON compliant"
+                    "Out of range float values are not JSON compliant: %S", obj
                     );
             return NULL;
         }