diff --git a/Lib/test/test_long.py b/Lib/test/test_long.py
index f336d49fa4f008..c206c9e02a9fbc 100644
--- a/Lib/test/test_long.py
+++ b/Lib/test/test_long.py
@@ -1693,5 +1693,22 @@ class MyInt(int):
         # GH-117195 -- This shouldn't crash
         object.__sizeof__(1)
 
+    def test_hash(self):
+        # gh-136599
+        self.assertEqual(hash(-1), -2)
+        self.assertEqual(hash(0), 0)
+        self.assertEqual(hash(10), 10)
+
+        self.assertEqual(hash(sys.hash_info.modulus - 2), sys.hash_info.modulus - 2)
+        self.assertEqual(hash(sys.hash_info.modulus - 1), sys.hash_info.modulus - 1)
+        self.assertEqual(hash(sys.hash_info.modulus), 0)
+        self.assertEqual(hash(sys.hash_info.modulus + 1), 1)
+
+        self.assertEqual(hash(-sys.hash_info.modulus - 2), -2)
+        self.assertEqual(hash(-sys.hash_info.modulus - 1), -2)
+        self.assertEqual(hash(-sys.hash_info.modulus), 0)
+        self.assertEqual(hash(-sys.hash_info.modulus + 1), - (sys.hash_info.modulus - 1))
+
+
 if __name__ == "__main__":
     unittest.main()
diff --git a/Misc/NEWS.d/next/Core_and_Builtins/2025-07-13-21-21-17.gh-issue-136599.sLhm2O.rst b/Misc/NEWS.d/next/Core_and_Builtins/2025-07-13-21-21-17.gh-issue-136599.sLhm2O.rst
new file mode 100644
index 00000000000000..9bcb13f9e20caf
--- /dev/null
+++ b/Misc/NEWS.d/next/Core_and_Builtins/2025-07-13-21-21-17.gh-issue-136599.sLhm2O.rst
@@ -0,0 +1 @@
+Improve performance of :class:`int` hash calculations.
diff --git a/Objects/longobject.c b/Objects/longobject.c
index 581db10b54ab57..e5e36cdb01b0eb 100644
--- a/Objects/longobject.c
+++ b/Objects/longobject.c
@@ -3676,7 +3676,20 @@ long_hash(PyObject *obj)
     }
     i = _PyLong_DigitCount(v);
     sign = _PyLong_NonCompactSign(v);
-    x = 0;
+
+    // unroll first two digits
+#if ( PyHASH_BITS > PyLong_SHIFT )
+    assert(i>=2);
+    --i;
+    x = v->long_value.ob_digit[i];
+    assert(x < _PyHASH_MODULUS);
+#endif
+#if ( PyHASH_BITS > (2 * PyLong_SHIFT) )
+    --i;
+    x = ((x << PyLong_SHIFT));
+    x += v->long_value.ob_digit[i];
+    assert(x < _PyHASH_MODULUS);
+#endif
     while (--i >= 0) {
         /* Here x is a quantity in the range [0, _PyHASH_MODULUS); we
            want to compute x * 2**PyLong_SHIFT + v->long_value.ob_digit[i] modulo