diff --git a/py/objdict.c b/py/objdict.c
index 55a612913..93ff1af90 100644
--- a/py/objdict.c
+++ b/py/objdict.c
@@ -43,6 +43,14 @@ static mp_obj_t dict_make_new(mp_obj_t type_in, uint n_args, uint n_kw, const mp
     return rt_build_map(0);
 }
 
+static mp_obj_t dict_unary_op(int op, mp_obj_t self_in) {
+    mp_obj_dict_t *self = self_in;
+    switch (op) {
+        case RT_UNARY_OP_NOT: if (self->map.used == 0) { return mp_const_true; } else { return mp_const_false; }
+        default: return MP_OBJ_NULL; // op not supported for None
+    }
+}
+
 static mp_obj_t dict_binary_op(int op, mp_obj_t lhs_in, mp_obj_t rhs_in) {
     mp_obj_dict_t *o = lhs_in;
     switch (op) {
@@ -436,6 +444,7 @@ const mp_obj_type_t dict_type = {
     "dict",
     .print = dict_print,
     .make_new = dict_make_new,
+    .unary_op = dict_unary_op,
     .binary_op = dict_binary_op,
     .getiter = dict_getiter,
     .methods = dict_type_methods,
diff --git a/py/objlist.c b/py/objlist.c
index 2e9a8705f..1e8930eee 100644
--- a/py/objlist.c
+++ b/py/objlist.c
@@ -119,6 +119,14 @@ static bool list_cmp_helper(int op, mp_obj_t self_in, mp_obj_t another_in) {
     return true;
 }
 
+static mp_obj_t list_unary_op(int op, mp_obj_t self_in) {
+    mp_obj_list_t *self = self_in;
+    switch (op) {
+        case RT_UNARY_OP_NOT: if (self->len == 0) { return mp_const_true; } else { return mp_const_false; }
+        default: return MP_OBJ_NULL; // op not supported for None
+    }
+}
+
 static mp_obj_t list_binary_op(int op, mp_obj_t lhs, mp_obj_t rhs) {
     mp_obj_list_t *o = lhs;
     switch (op) {
@@ -395,6 +403,7 @@ const mp_obj_type_t list_type = {
     "list",
     .print = list_print,
     .make_new = list_make_new,
+    .unary_op = list_unary_op,
     .binary_op = list_binary_op,
     .getiter = list_getiter,
     .methods = list_type_methods,
diff --git a/py/objnone.c b/py/objnone.c
index ecc7c4b4e..4151403b2 100644
--- a/py/objnone.c
+++ b/py/objnone.c
@@ -6,19 +6,28 @@
 #include "mpconfig.h"
 #include "qstr.h"
 #include "obj.h"
+#include "runtime0.h"
 
 typedef struct _mp_obj_none_t {
     mp_obj_base_t base;
 } mp_obj_none_t;
 
-void none_print(void (*print)(void *env, const char *fmt, ...), void *env, mp_obj_t self_in, mp_print_kind_t kind) {
+static void none_print(void (*print)(void *env, const char *fmt, ...), void *env, mp_obj_t self_in, mp_print_kind_t kind) {
     print(env, "None");
 }
 
+static mp_obj_t none_unary_op(int op, mp_obj_t o_in) {
+    switch (op) {
+        case RT_UNARY_OP_NOT: return mp_const_true;
+        default: return MP_OBJ_NULL; // op not supported for None
+    }
+}
+
 const mp_obj_type_t none_type = {
     { &mp_const_type },
     "NoneType",
     .print = none_print,
+    .unary_op = none_unary_op,
 };
 
 static const mp_obj_none_t none_obj = {{&none_type}};
diff --git a/py/objtuple.c b/py/objtuple.c
index ec35ef855..754fe4b66 100644
--- a/py/objtuple.c
+++ b/py/objtuple.c
@@ -73,6 +73,14 @@ static mp_obj_t tuple_make_new(mp_obj_t type_in, uint n_args, uint n_kw, const m
     }
 }
 
+static mp_obj_t tuple_unary_op(int op, mp_obj_t self_in) {
+    mp_obj_tuple_t *self = self_in;
+    switch (op) {
+        case RT_UNARY_OP_NOT: if (self->len == 0) { return mp_const_true; } else { return mp_const_false; }
+        default: return MP_OBJ_NULL; // op not supported for None
+    }
+}
+
 static mp_obj_t tuple_binary_op(int op, mp_obj_t lhs, mp_obj_t rhs) {
     mp_obj_tuple_t *o = lhs;
     switch (op) {
@@ -97,6 +105,7 @@ const mp_obj_type_t tuple_type = {
     "tuple",
     .print = tuple_print,
     .make_new = tuple_make_new,
+    .unary_op = tuple_unary_op,
     .binary_op = tuple_binary_op,
     .getiter = tuple_getiter,
 };
diff --git a/py/runtime.c b/py/runtime.c
index 8ad98d5f1..ba80480ae 100644
--- a/py/runtime.c
+++ b/py/runtime.c
@@ -481,7 +481,7 @@ mp_obj_t rt_unary_op(int op, mp_obj_t arg) {
     if (MP_OBJ_IS_SMALL_INT(arg)) {
         mp_small_int_t val = MP_OBJ_SMALL_INT_VALUE(arg);
         switch (op) {
-            case RT_UNARY_OP_NOT: if (val != 0) { return mp_const_true;} else { return mp_const_false; }
+            case RT_UNARY_OP_NOT: if (val == 0) { return mp_const_true;} else { return mp_const_false; }
             case RT_UNARY_OP_POSITIVE: break;
             case RT_UNARY_OP_NEGATIVE: val = -val; break;
             case RT_UNARY_OP_INVERT: val = ~val; break;
diff --git a/tests/basics/unary_op.py b/tests/basics/unary_op.py
new file mode 100644
index 000000000..9846285d5
--- /dev/null
+++ b/tests/basics/unary_op.py
@@ -0,0 +1,12 @@
+print(not None)
+print(not False)
+print(not True)
+print(not 0)
+print(not 1)
+print(not -1)
+print(not ())
+print(not (1,))
+print(not [])
+print(not [1,])
+print(not {})
+print(not {1:1})