diff --git a/src/core/border_router/routing_manager.cpp b/src/core/border_router/routing_manager.cpp
index 2b073b4b987..2af95e2bc36 100644
--- a/src/core/border_router/routing_manager.cpp
+++ b/src/core/border_router/routing_manager.cpp
@@ -362,7 +362,11 @@ void RoutingManager::Stop(void)
 
     SendRouterAdvertisement(kInvalidateAllPrevPrefixes);
 
+#if OPENTHREAD_CONFIG_BORDER_ROUTING_USE_HEAP_ENABLE
+    mAdvertisedPrefixes.Free();
+#else
     mAdvertisedPrefixes.Clear();
+#endif
 
     mDiscoveredPrefixTable.RemoveAllEntries();
     mDiscoveredPrefixStaleTimer.Stop();
diff --git a/src/core/border_router/routing_manager.hpp b/src/core/border_router/routing_manager.hpp
index c78862931ba..55da201915b 100644
--- a/src/core/border_router/routing_manager.hpp
+++ b/src/core/border_router/routing_manager.hpp
@@ -54,6 +54,7 @@
 #include "common/array.hpp"
 #include "common/error.hpp"
 #include "common/heap_allocatable.hpp"
+#include "common/heap_array.hpp"
 #include "common/linked_list.hpp"
 #include "common/locator.hpp"
 #include "common/message.hpp"
@@ -954,7 +955,12 @@ class RoutingManager : public InstanceLocator
 
     typedef Ip6::Prefix OnMeshPrefix;
 
-    class OnMeshPrefixArray : public Array<OnMeshPrefix, kMaxOnMeshPrefixes>
+    class OnMeshPrefixArray :
+#if OPENTHREAD_CONFIG_BORDER_ROUTING_USE_HEAP_ENABLE
+        public Heap::Array<OnMeshPrefix>
+#else
+        public Array<OnMeshPrefix, kMaxOnMeshPrefixes>
+#endif
     {
     public:
         void Add(const OnMeshPrefix &aPrefix);
diff --git a/tests/toranj/openthread-core-toranj-config-posix.h b/tests/toranj/openthread-core-toranj-config-posix.h
index 95cf37ac372..60e86777fcc 100644
--- a/tests/toranj/openthread-core-toranj-config-posix.h
+++ b/tests/toranj/openthread-core-toranj-config-posix.h
@@ -47,4 +47,7 @@
 
 #define OPENTHREAD_POSIX_CONFIG_SPINEL_HDLC_INTERFACE_ENABLE 1
 
+// Disabled explicitly on posix `toranj` to validate the build with this config
+#define OPENTHREAD_CONFIG_BORDER_ROUTING_USE_HEAP_ENABLE 0
+
 #endif /* OPENTHREAD_CORE_TORANJ_CONFIG_POSIX_H_ */
diff --git a/tests/toranj/openthread-core-toranj-config-simulation.h b/tests/toranj/openthread-core-toranj-config-simulation.h
index 234465a6f09..8a1063c5cbd 100644
--- a/tests/toranj/openthread-core-toranj-config-simulation.h
+++ b/tests/toranj/openthread-core-toranj-config-simulation.h
@@ -59,6 +59,8 @@
 
 #define OPENTHREAD_CONFIG_HEAP_EXTERNAL_ENABLE 1
 
+#define OPENTHREAD_CONFIG_BORDER_ROUTING_USE_HEAP_ENABLE 1
+
 #define OPENTHREAD_CONFIG_RADIO_STATS_ENABLE 0
 
 #endif /* OPENTHREAD_CORE_TORANJ_CONFIG_SIMULATION_H_ */