diff --git a/src/NPoco/Database.cs b/src/NPoco/Database.cs
index d4cd6273..f90f6d7e 100644
--- a/src/NPoco/Database.cs
+++ b/src/NPoco/Database.cs
@@ -632,7 +632,11 @@ public T ExecuteScalar<T>(string sql, CommandType commandType, params object[] a
                     Type t = typeof(T);
                     Type u = Nullable.GetUnderlyingType(t);
 
-                    return (T)Convert.ChangeType(val, u ?? t);
+                    var converter = MappingHelper.GetConverter(Mappers, null, val.GetType(), t);
+
+                    return converter != null
+                        ? (T)converter.Invoke(val)
+                        : (T)Convert.ChangeType(val, u ?? t);
                 }
             }
             catch (Exception x)