diff --git a/changes.rst b/changes.rst
index 7a9e884bd..453ead38c 100644
--- a/changes.rst
+++ b/changes.rst
@@ -51,6 +51,7 @@ Bug fixes:
    (:bugref:`679`).
 -  Fix common subexpression elimination for expressions used in incompatible
    contexts (:bugref:`666`).
+-  Add missing ``::promise_total`` to functional version of ``nvalue``.
 
 Changes in the IDE:
 ^^^^^^^^^^^^^^^^^^^
diff --git a/share/minizinc/std/nvalue_fn.mzn b/share/minizinc/std/nvalue_fn.mzn
index 0cdfbdb31..4562b2e5b 100644
--- a/share/minizinc/std/nvalue_fn.mzn
+++ b/share/minizinc/std/nvalue_fn.mzn
@@ -3,5 +3,5 @@ include "nvalue.mzn";
 /** @group globals.alldifferent
   Returns the number of distinct values in \a x.
 */
-function var int: nvalue(array[$X] of var int: x) =
+function var int: nvalue(array[$X] of var int: x) :: promise_total =
   let { var 0..length(x): n::is_defined_var; constraint nvalue(n,x)::defines_var(n); } in n;
diff --git a/tests/spec/unit/globals/nvalue/nvalue_total.mzn b/tests/spec/unit/globals/nvalue/nvalue_total.mzn
new file mode 100644
index 000000000..b4f6f14c2
--- /dev/null
+++ b/tests/spec/unit/globals/nvalue/nvalue_total.mzn
@@ -0,0 +1,12 @@
+/***
+!Test
+solvers: [gecode]
+expected: !Result
+  solution: !Solution
+    l1: 0
+***/
+
+include "nvalue_fn.mzn";
+
+array[1..10] of var 0..10: X;
+int: l1 :: output = lb(nvalue(X));