diff --git a/.github/workflows/simulation.yml b/.github/workflows/simulation.yml
index 674afed25..831a9181e 100644
--- a/.github/workflows/simulation.yml
+++ b/.github/workflows/simulation.yml
@@ -194,6 +194,9 @@ jobs:
 
   cli-mtd:
     runs-on: ubuntu-18.04
+    strategy:
+      matrix:
+        message_use_heap: [0, 1]
     env:
       CFLAGS: -m32
       CXXFLAGS: -m32
@@ -202,6 +205,7 @@ jobs:
       REFERENCE_DEVICE: 1
       USE_MTD: 1
       VIRTUAL_TIME: 1
+      MESSAGE_USE_HEAP: ${{ matrix.message_use_heap }}
     steps:
     - uses: actions/checkout@v2
     - name: Bootstrap
diff --git a/etc/cmake/options.cmake b/etc/cmake/options.cmake
index ce0c180fe..ea3479006 100644
--- a/etc/cmake/options.cmake
+++ b/etc/cmake/options.cmake
@@ -146,6 +146,11 @@ if(OT_DUA)
     target_compile_definitions(ot-config INTERFACE "OPENTHREAD_CONFIG_DUA_ENABLE=1")
 endif()
 
+option(OT_MESSAGE_USE_HEAP "enable heap allocator for message buffers")
+if(OT_MESSAGE_USE_HEAP)
+    target_compile_definitions(ot-config INTERFACE "OPENTHREAD_CONFIG_MESSAGE_USE_HEAP_ENABLE=1")
+endif()
+
 option(OT_MLR "enable Multicast Listener Registration feature for Thread 1.2")
 if(OT_MLR)
     target_compile_definitions(ot-config INTERFACE "OPENTHREAD_CONFIG_MLR_ENABLE=1")
diff --git a/etc/gn/openthread.gni b/etc/gn/openthread.gni
index 68ede5dc8..e69261201 100644
--- a/etc/gn/openthread.gni
+++ b/etc/gn/openthread.gni
@@ -162,6 +162,9 @@ if (openthread_enable_core_config_args) {
     # Enable mac filter support
     openthread_config_mac_filter_enable = false
 
+    # Enable use built-in heap for message buffers
+    openthread_config_message_use_heap = false
+
     # Enable MLE long routes extension (experimental, breaks Thread conformance]
     openthread_config_mle_long_routes_enable = false
 
diff --git a/examples/common-switches.mk b/examples/common-switches.mk
index 0649a61e0..a9630c18d 100644
--- a/examples/common-switches.mk
+++ b/examples/common-switches.mk
@@ -61,6 +61,7 @@ LOG_OUTPUT          ?= APP
 endif
 LINK_RAW            ?= 0
 MAC_FILTER          ?= 0
+MESSAGE_USE_HEAP    ?= 0
 MLE_LONG_ROUTES     ?= 0
 MLR                 ?= 0
 MTD_NETDIAG         ?= 0
@@ -214,6 +215,10 @@ ifeq ($(MAC_FILTER),1)
 COMMONCFLAGS                   += -DOPENTHREAD_CONFIG_MAC_FILTER_ENABLE=1
 endif
 
+ifeq ($(MESSAGE_USE_HEAP),1)
+COMMONCFLAGS                   += -DOPENTHREAD_CONFIG_MESSAGE_USE_HEAP_ENABLE=1
+endif
+
 # Enable MLE long routes extension (experimental, breaks Thread conformance)
 ifeq ($(MLE_LONG_ROUTES),1)
 COMMONCFLAGS                   += -DOPENTHREAD_CONFIG_MLE_LONG_ROUTES_ENABLE=1
diff --git a/script/check-size b/script/check-size
index 4387e5432..bd1a554a9 100755
--- a/script/check-size
+++ b/script/check-size
@@ -120,6 +120,7 @@ size_nrf52840_version()
         "JOINER=1"
         "LINK_RAW=1"
         "MAC_FILTER=1"
+        "MESSAGE_USE_HEAP=1"
         "MTD_NETDIAG=1"
         "SERVICE=1"
         "SLAAC=1"
diff --git a/script/test b/script/test
index 7de8fe87e..80b328cd0 100755
--- a/script/test
+++ b/script/test
@@ -48,7 +48,7 @@ readonly VERBOSE="${VERBOSE:-0}"
 build_simulation()
 {
     local version="$1"
-    local options=("-DOT_THREAD_VERSION=${version}" "-DBUILD_TESTING=ON" "-DOT_REFERENCE_DEVICE=ON")
+    local options=("-DOT_MESSAGE_USE_HEAP=ON" "-DOT_THREAD_VERSION=${version}" "-DBUILD_TESTING=ON" "-DOT_REFERENCE_DEVICE=ON")
 
     if [[ ${version} == "1.2" ]]; then
         options+=("-DOT_DUA=ON")
@@ -87,7 +87,7 @@ build_simulation()
 build_posix()
 {
     local version="$1"
-    local options=("-DOT_THREAD_VERSION=${version}" "-DBUILD_TESTING=ON")
+    local options=("-DOT_MESSAGE_USE_HEAP=ON" "-DOT_THREAD_VERSION=${version}" "-DBUILD_TESTING=ON")
 
     if [[ ${version} == "1.2" ]]; then
         options+=("-DOT_DUA=ON")
diff --git a/src/core/BUILD.gn b/src/core/BUILD.gn
index d6e565d44..859a19935 100644
--- a/src/core/BUILD.gn
+++ b/src/core/BUILD.gn
@@ -176,6 +176,10 @@ if (openthread_enable_core_config_args) {
       defines += [ "OPENTHREAD_CONFIG_MAC_FILTER_ENABLE=1" ]
     }
 
+    if (openthread_config_message_use_heap) {
+      defines += [ "OPENTHREAD_CONFIG_MESSAGE_USE_HEAP_ENABLE=1" ]
+    }
+
     if (openthread_config_mle_long_routes_enable) {
       defines += [ "OPENTHREAD_CONFIG_MLE_LONG_ROUTES_ENABLE=1" ]
     }
diff --git a/src/core/common/message.cpp b/src/core/common/message.cpp
index 54e582604..1f1bfe9cb 100644
--- a/src/core/common/message.cpp
+++ b/src/core/common/message.cpp
@@ -41,11 +41,12 @@
 #include "net/checksum.hpp"
 #include "net/ip6.hpp"
 
+#if OPENTHREAD_MTD || OPENTHREAD_FTD
 namespace ot {
 
 MessagePool::MessagePool(Instance &aInstance)
     : InstanceLocator(aInstance)
-#if !OPENTHREAD_CONFIG_PLATFORM_MESSAGE_MANAGEMENT
+#if !OPENTHREAD_CONFIG_PLATFORM_MESSAGE_MANAGEMENT && !OPENTHREAD_CONFIG_MESSAGE_USE_HEAP_ENABLE
     , mNumFreeBuffers(kNumBuffers)
 #endif
 {
@@ -103,21 +104,24 @@ Buffer *MessagePool::NewBuffer(Message::Priority aPriority)
 {
     Buffer *buffer = nullptr;
 
-    SuccessOrExit(ReclaimBuffers(1, aPriority));
-
-#if OPENTHREAD_CONFIG_PLATFORM_MESSAGE_MANAGEMENT
-
-    buffer = static_cast<Buffer *>(otPlatMessagePoolNew(&GetInstance()));
-
+    while ((
+#if OPENTHREAD_CONFIG_MESSAGE_USE_HEAP_ENABLE
+               buffer = static_cast<Buffer *>(GetInstance().HeapCAlloc(sizeof(Buffer), 1))
+#elif OPENTHREAD_CONFIG_PLATFORM_MESSAGE_MANAGEMENT
+               buffer = static_cast<Buffer *>(otPlatMessagePoolNew(&GetInstance()))
 #else
-
-    buffer = mBufferPool.Allocate();
-    VerifyOrExit(buffer != nullptr);
-
-    mNumFreeBuffers--;
-    buffer->SetNextBuffer(nullptr);
-
+               buffer = mBufferPool.Allocate()
 #endif
+                   ) == nullptr)
+    {
+        SuccessOrExit(ReclaimBuffers(aPriority));
+    }
+
+#if !OPENTHREAD_CONFIG_PLATFORM_MESSAGE_MANAGEMENT && !OPENTHREAD_CONFIG_MESSAGE_USE_HEAP_ENABLE
+    mNumFreeBuffers--;
+#endif
+
+    buffer->SetNextBuffer(nullptr);
 
 exit:
     if (buffer == nullptr)
@@ -133,7 +137,9 @@ void MessagePool::FreeBuffers(Buffer *aBuffer)
     while (aBuffer != nullptr)
     {
         Buffer *next = aBuffer->GetNextBuffer();
-#if OPENTHREAD_CONFIG_PLATFORM_MESSAGE_MANAGEMENT
+#if OPENTHREAD_CONFIG_MESSAGE_USE_HEAP_ENABLE
+        GetInstance().HeapFree(aBuffer);
+#elif OPENTHREAD_CONFIG_PLATFORM_MESSAGE_MANAGEMENT
         otPlatMessagePoolFree(&GetInstance(), aBuffer);
 #else
         mBufferPool.Free(*aBuffer);
@@ -143,30 +149,18 @@ void MessagePool::FreeBuffers(Buffer *aBuffer)
     }
 }
 
-otError MessagePool::ReclaimBuffers(int aNumBuffers, Message::Priority aPriority)
+otError MessagePool::ReclaimBuffers(Message::Priority aPriority)
 {
-#if OPENTHREAD_MTD || OPENTHREAD_FTD
-    while (aNumBuffers > GetFreeBufferCount())
-    {
-        SuccessOrExit(Get<MeshForwarder>().EvictMessage(aPriority));
-    }
-
-exit:
-#else
-    OT_UNUSED_VARIABLE(aPriority);
-#endif
-
-    // First comparison is to get around issues with comparing
-    // signed and unsigned numbers, if aNumBuffers is negative then
-    // the second comparison wont be attempted.
-    return (aNumBuffers < 0 || aNumBuffers <= GetFreeBufferCount()) ? OT_ERROR_NONE : OT_ERROR_NO_BUFS;
+    return Get<MeshForwarder>().EvictMessage(aPriority);
 }
 
 uint16_t MessagePool::GetFreeBufferCount(void) const
 {
     uint16_t rval;
 
-#if OPENTHREAD_CONFIG_PLATFORM_MESSAGE_MANAGEMENT
+#if OPENTHREAD_CONFIG_MESSAGE_USE_HEAP_ENABLE
+    rval = static_cast<uint16_t>(GetInstance().GetHeap().GetFreeSize() / sizeof(Buffer));
+#elif OPENTHREAD_CONFIG_PLATFORM_MESSAGE_MANAGEMENT
     rval = otPlatMessagePoolNumFreeBuffers(&GetInstance());
 #else
     rval = mNumFreeBuffers;
@@ -254,23 +248,9 @@ otError Message::SetLength(uint16_t aLength)
 {
     otError  error              = OT_ERROR_NONE;
     uint16_t totalLengthRequest = GetReserved() + aLength;
-    uint16_t totalLengthCurrent = GetReserved() + GetLength();
-    int      bufs               = 0;
 
     VerifyOrExit(totalLengthRequest >= GetReserved(), error = OT_ERROR_INVALID_ARGS);
 
-    if (totalLengthRequest > kHeadBufferDataSize)
-    {
-        bufs = (((totalLengthRequest - kHeadBufferDataSize) - 1) / kBufferDataSize) + 1;
-    }
-
-    if (totalLengthCurrent > kHeadBufferDataSize)
-    {
-        bufs -= (((totalLengthCurrent - kHeadBufferDataSize) - 1) / kBufferDataSize) + 1;
-    }
-
-    SuccessOrExit(error = GetMessagePool()->ReclaimBuffers(bufs, GetPriority()));
-
     SuccessOrExit(error = ResizeMessage(totalLengthRequest));
     GetMetadata().mLength = aLength;
 
@@ -871,3 +851,4 @@ void PriorityQueue::GetInfo(uint16_t &aMessageCount, uint16_t &aBufferCount) con
 }
 
 } // namespace ot
+#endif // OPENTHREAD_MTD || OPENTHREAD_FTD
diff --git a/src/core/common/message.hpp b/src/core/common/message.hpp
index 10b602a68..e98072dae 100644
--- a/src/core/common/message.hpp
+++ b/src/core/common/message.hpp
@@ -1471,9 +1471,9 @@ public:
 private:
     Buffer *NewBuffer(Message::Priority aPriority);
     void    FreeBuffers(Buffer *aBuffer);
-    otError ReclaimBuffers(int aNumBuffers, Message::Priority aPriority);
+    otError ReclaimBuffers(Message::Priority aPriority);
 
-#if OPENTHREAD_CONFIG_PLATFORM_MESSAGE_MANAGEMENT == 0
+#if !OPENTHREAD_CONFIG_PLATFORM_MESSAGE_MANAGEMENT && !OPENTHREAD_CONFIG_MESSAGE_USE_HEAP_ENABLE
     uint16_t                  mNumFreeBuffers;
     Pool<Buffer, kNumBuffers> mBufferPool;
 #endif
diff --git a/src/core/config/openthread-core-config-check.h b/src/core/config/openthread-core-config-check.h
index c3cf4f5ac..aefd661df 100644
--- a/src/core/config/openthread-core-config-check.h
+++ b/src/core/config/openthread-core-config-check.h
@@ -546,4 +546,13 @@
        "(and OPENTHREAD_CONFIG_LOG_DEFINE_AS_MACRO_ONLY)"
 #endif
 
+#if OPENTHREAD_CONFIG_MESSAGE_USE_HEAP_ENABLE
+#if !OPENTHREAD_CONFIG_DTLS_ENABLE
+#error "OPENTHREAD_CONFIG_MESSAGE_USE_HEAP_ENABLE is strongly discouraged when OPENTHREAD_CONFIG_DTLS_ENABLE is off."
+#endif
+#if OPENTHREAD_CONFIG_PLATFORM_MESSAGE_MANAGEMENT
+#error "OPENTHREAD_CONFIG_MESSAGE_USE_HEAP_ENABLE conflicts with OPENTHREAD_CONFIG_PLATFORM_MESSAGE_MANAGEMENT."
+#endif
+#endif
+
 #endif // OPENTHREAD_CORE_CONFIG_CHECK_H_
diff --git a/src/core/config/openthread-core-default-config.h b/src/core/config/openthread-core-default-config.h
index d67c500fb..d8b1a2e42 100644
--- a/src/core/config/openthread-core-default-config.h
+++ b/src/core/config/openthread-core-default-config.h
@@ -127,6 +127,18 @@
 #define OPENTHREAD_CONFIG_UDP_FORWARD_ENABLE 0
 #endif
 
+/**
+ * @def OPENTHREAD_CONFIG_MESSAGE_USE_HEAP_ENABLE
+ *
+ * Whether use heap allocator for message buffers.
+ *
+ * @note If this is set, OPENTHREAD_CONFIG_NUM_MESSAGE_BUFFERS is ignored.
+ *
+ */
+#ifndef OPENTHREAD_CONFIG_MESSAGE_USE_HEAP_ENABLE
+#define OPENTHREAD_CONFIG_MESSAGE_USE_HEAP_ENABLE 0
+#endif
+
 /**
  * @def OPENTHREAD_CONFIG_NUM_MESSAGE_BUFFERS
  *
diff --git a/tests/toranj/openthread-core-toranj-config.h b/tests/toranj/openthread-core-toranj-config.h
index 5b8d0ef31..df9d8dfca 100644
--- a/tests/toranj/openthread-core-toranj-config.h
+++ b/tests/toranj/openthread-core-toranj-config.h
@@ -119,6 +119,14 @@
  */
 #define OPENTHREAD_CONFIG_NUM_MESSAGE_BUFFERS 256
 
+/**
+ * @def OPENTHREAD_CONFIG_MESSAGE_USE_HEAP_ENABLE
+ *
+ * Whether use heap allocator for message buffers.
+ *
+ */
+#define OPENTHREAD_CONFIG_MESSAGE_USE_HEAP_ENABLE 1
+
 /**
  * @def OPENTHREAD_CONFIG_TMF_ADDRESS_CACHE_ENTRIES
  *