diff --git a/rosidl_runtime_c/src/primitives_sequence_functions.c b/rosidl_runtime_c/src/primitives_sequence_functions.c
index 5884c8e69..11c7fd02a 100644
--- a/rosidl_runtime_c/src/primitives_sequence_functions.c
+++ b/rosidl_runtime_c/src/primitives_sequence_functions.c
@@ -16,6 +16,8 @@
 #include <stdint.h>
 #include <stdlib.h>
 
+#include <rcutils/allocator.h>
+
 #include "rosidl_runtime_c/primitives_sequence_functions.h"
 
 #define ROSIDL_GENERATOR_C__DEFINE_PRIMITIVE_SEQUENCE_FUNCTIONS(STRUCT_NAME, TYPE_NAME) \
@@ -27,7 +29,8 @@
     } \
     TYPE_NAME * data = NULL; \
     if (size) { \
-      data = malloc(sizeof(TYPE_NAME) * size); \
+      rcutils_allocator_t allocator = rcutils_get_default_allocator(); \
+      data = allocator.allocate(sizeof(TYPE_NAME) * size, allocator.state); \
       if (!data) { \
         return false; \
       } \
@@ -47,7 +50,8 @@
     if (sequence->data) { \
       /* ensure that data and capacity values are consistent */ \
       assert(sequence->capacity > 0); \
-      free(sequence->data); \
+      rcutils_allocator_t allocator = rcutils_get_default_allocator(); \
+      allocator.deallocate(sequence->data, allocator.state); \
       sequence->data = NULL; \
       sequence->size = 0; \
       sequence->capacity = 0; \
diff --git a/rosidl_runtime_c/src/string_functions.c b/rosidl_runtime_c/src/string_functions.c
index 2e4ef3464..9f47cefa5 100644
--- a/rosidl_runtime_c/src/string_functions.c
+++ b/rosidl_runtime_c/src/string_functions.c
@@ -19,6 +19,7 @@
 #include <string.h>
 #include <stdio.h>
 
+#include <rcutils/allocator.h>
 #include "rcutils/macros.h"
 
 bool
@@ -29,7 +30,8 @@ rosidl_runtime_c__String__init(rosidl_runtime_c__String * str)
   if (!str) {
     return false;
   }
-  str->data = malloc(1);
+  rcutils_allocator_t allocator = rcutils_get_default_allocator();
+  str->data = allocator.allocate(1, allocator.state);
   if (!str->data) {
     return false;
   }
@@ -53,7 +55,8 @@ rosidl_runtime_c__String__fini(rosidl_runtime_c__String * str)
         "Exiting.\n");
       exit(-1);
     }
-    free(str->data);
+    rcutils_allocator_t allocator = rcutils_get_default_allocator();
+    allocator.deallocate(str->data, allocator.state);
     str->data = NULL;
     str->size = 0;
     str->capacity = 0;
@@ -89,7 +92,8 @@ rosidl_runtime_c__String__assignn(
   if (n == SIZE_MAX) {
     return false;
   }
-  char * data = realloc(str->data, n + 1);
+  rcutils_allocator_t allocator = rcutils_get_default_allocator();
+  char * data = allocator.reallocate(str->data, n + 1, allocator.state);
   if (!data) {
     return false;
   }
@@ -124,7 +128,9 @@ rosidl_runtime_c__String__Sequence__init(
   }
   rosidl_runtime_c__String * data = NULL;
   if (size) {
-    data = (rosidl_runtime_c__String *)calloc(size, sizeof(rosidl_runtime_c__String));
+    rcutils_allocator_t allocator = rcutils_get_default_allocator();
+    data = (rosidl_runtime_c__String *)allocator.zero_allocate(
+      size, sizeof(rosidl_runtime_c__String), allocator.state);
     if (!data) {
       return false;
     }
@@ -135,7 +141,7 @@ rosidl_runtime_c__String__Sequence__init(
         for (; i-- > 0; ) {
           rosidl_runtime_c__String__fini(&data[i]);
         }
-        free(data);
+        allocator.deallocate(data, allocator.state);
         return false;
       }
     }
@@ -160,7 +166,8 @@ rosidl_runtime_c__String__Sequence__fini(
     for (size_t i = 0; i < sequence->capacity; ++i) {
       rosidl_runtime_c__String__fini(&sequence->data[i]);
     }
-    free(sequence->data);
+    rcutils_allocator_t allocator = rcutils_get_default_allocator();
+    allocator.deallocate(sequence->data, allocator.state);
     sequence->data = NULL;
     sequence->size = 0;
     sequence->capacity = 0;
@@ -174,14 +181,16 @@ rosidl_runtime_c__String__Sequence__fini(
 rosidl_runtime_c__String__Sequence *
 rosidl_runtime_c__String__Sequence__create(size_t size)
 {
+  rcutils_allocator_t allocator = rcutils_get_default_allocator();
   rosidl_runtime_c__String__Sequence * sequence =
-    (rosidl_runtime_c__String__Sequence *)malloc(sizeof(rosidl_runtime_c__String__Sequence));
+    (rosidl_runtime_c__String__Sequence *)allocator.allocate(
+        sizeof(rosidl_runtime_c__String__Sequence), allocator.state);
   if (!sequence) {
     return NULL;
   }
   bool success = rosidl_runtime_c__String__Sequence__init(sequence, size);
   if (!success) {
-    free(sequence);
+    allocator.deallocate(sequence, allocator.state);
     return NULL;
   }
   return sequence;
@@ -194,5 +203,6 @@ rosidl_runtime_c__String__Sequence__destroy(
   if (sequence) {
     rosidl_runtime_c__String__Sequence__fini(sequence);
   }
-  free(sequence);
+  rcutils_allocator_t allocator = rcutils_get_default_allocator();
+  allocator.deallocate(sequence, allocator.state);
 }
diff --git a/rosidl_runtime_c/src/u16string_functions.c b/rosidl_runtime_c/src/u16string_functions.c
index 9ae5e4faf..d55c42538 100644
--- a/rosidl_runtime_c/src/u16string_functions.c
+++ b/rosidl_runtime_c/src/u16string_functions.c
@@ -19,6 +19,7 @@
 #include <string.h>
 #include <stdio.h>
 
+#include <rcutils/allocator.h>
 #include "rcutils/macros.h"
 
 bool
@@ -29,7 +30,8 @@ rosidl_runtime_c__U16String__init(rosidl_runtime_c__U16String * str)
   if (!str) {
     return false;
   }
-  str->data = malloc(sizeof(uint16_t));
+  rcutils_allocator_t allocator = rcutils_get_default_allocator();
+  str->data = allocator.allocate(sizeof(uint16_t), allocator.state);
   if (!str->data) {
     return false;
   }
@@ -53,7 +55,8 @@ rosidl_runtime_c__U16String__fini(rosidl_runtime_c__U16String * str)
         "Exiting.\n");
       exit(-1);
     }
-    free(str->data);
+    rcutils_allocator_t allocator = rcutils_get_default_allocator();
+    allocator.deallocate(str->data, allocator.state);
     str->data = NULL;
     str->size = 0;
     str->capacity = 0;
@@ -89,7 +92,8 @@ rosidl_runtime_c__U16String__assignn(
   if (n == SIZE_MAX) {
     return false;
   }
-  uint16_t * data = realloc(str->data, (n + 1) * sizeof(uint16_t));
+  rcutils_allocator_t allocator = rcutils_get_default_allocator();
+  uint16_t * data = allocator.reallocate(str->data, (n + 1) * sizeof(uint16_t), allocator.state);
   if (!data) {
     return false;
   }
@@ -145,7 +149,8 @@ rosidl_runtime_c__U16String__resize(
   if (n > SIZE_MAX / sizeof(uint16_t) - 1) {
     return false;
   }
-  uint16_t * data = realloc(str->data, (n + 1) * sizeof(uint16_t));
+  rcutils_allocator_t allocator = rcutils_get_default_allocator();
+  uint16_t * data = allocator.reallocate(str->data, (n + 1) * sizeof(uint16_t), allocator.state);
   if (!data) {
     return false;
   }
@@ -167,7 +172,9 @@ rosidl_runtime_c__U16String__Sequence__init(
   }
   rosidl_runtime_c__U16String * data = NULL;
   if (size) {
-    data = (rosidl_runtime_c__U16String *)malloc(size * sizeof(rosidl_runtime_c__U16String));
+    rcutils_allocator_t allocator = rcutils_get_default_allocator();
+    data = (rosidl_runtime_c__U16String *)allocator.allocate(
+      size * sizeof(rosidl_runtime_c__U16String), allocator.state);
     if (!data) {
       return false;
     }
@@ -178,7 +185,7 @@ rosidl_runtime_c__U16String__Sequence__init(
         for (; i-- > 0; ) {
           rosidl_runtime_c__U16String__fini(&data[i]);
         }
-        free(data);
+        allocator.deallocate(data, allocator.state);
         return false;
       }
     }
@@ -203,7 +210,8 @@ rosidl_runtime_c__U16String__Sequence__fini(
     for (size_t i = 0; i < sequence->capacity; ++i) {
       rosidl_runtime_c__U16String__fini(&sequence->data[i]);
     }
-    free(sequence->data);
+    rcutils_allocator_t allocator = rcutils_get_default_allocator();
+    allocator.deallocate(sequence->data, allocator.state);
     sequence->data = NULL;
     sequence->size = 0;
     sequence->capacity = 0;
@@ -217,15 +225,16 @@ rosidl_runtime_c__U16String__Sequence__fini(
 rosidl_runtime_c__U16String__Sequence *
 rosidl_runtime_c__U16String__Sequence__create(size_t size)
 {
+  rcutils_allocator_t allocator = rcutils_get_default_allocator();
   rosidl_runtime_c__U16String__Sequence * sequence =
-    (rosidl_runtime_c__U16String__Sequence *)malloc(
-    sizeof(rosidl_runtime_c__U16String__Sequence));
+    (rosidl_runtime_c__U16String__Sequence *)allocator.allocate(
+    sizeof(rosidl_runtime_c__U16String__Sequence), allocator.state);
   if (!sequence) {
     return NULL;
   }
   bool success = rosidl_runtime_c__U16String__Sequence__init(sequence, size);
   if (!success) {
-    free(sequence);
+    allocator.deallocate(sequence, allocator.state);
     return NULL;
   }
   return sequence;
@@ -238,5 +247,6 @@ rosidl_runtime_c__U16String__Sequence__destroy(
   if (sequence) {
     rosidl_runtime_c__U16String__Sequence__fini(sequence);
   }
-  free(sequence);
+  rcutils_allocator_t allocator = rcutils_get_default_allocator();
+  allocator.deallocate(sequence, allocator.state);
 }