diff --git a/samples/bluetooth/mesh/microbit_gatt.conf b/samples/bluetooth/mesh/microbit_gatt.conf
index a0682b0771..c3fd28ab23 100644
--- a/samples/bluetooth/mesh/microbit_gatt.conf
+++ b/samples/bluetooth/mesh/microbit_gatt.conf
@@ -1,4 +1,5 @@
 #CONFIG_INIT_STACKS=y
+CONFIG_ISR_STACK_SIZE=768
 CONFIG_MAIN_STACK_SIZE=320
 CONFIG_IDLE_STACK_SIZE=128
 CONFIG_DISPLAY=y
diff --git a/samples/bluetooth/mesh/nrf51_qfaa.conf b/samples/bluetooth/mesh/nrf51_qfaa.conf
index 60838aa7cf..b5ebd7f820 100644
--- a/samples/bluetooth/mesh/nrf51_qfaa.conf
+++ b/samples/bluetooth/mesh/nrf51_qfaa.conf
@@ -1,4 +1,5 @@
 CONFIG_INIT_STACKS=y
+CONFIG_ISR_STACK_SIZE=512
 CONFIG_MAIN_STACK_SIZE=512
 
 CONFIG_BT=y
diff --git a/samples/bluetooth/mesh/prj_bbc_microbit.conf b/samples/bluetooth/mesh/prj_bbc_microbit.conf
index 7f37c836ba..cf7212fd0e 100644
--- a/samples/bluetooth/mesh/prj_bbc_microbit.conf
+++ b/samples/bluetooth/mesh/prj_bbc_microbit.conf
@@ -1,4 +1,5 @@
 CONFIG_INIT_STACKS=y
+CONFIG_ISR_STACK_SIZE=768
 CONFIG_MAIN_STACK_SIZE=512
 CONFIG_DISPLAY=y
 CONFIG_MICROBIT_DISPLAY=y
diff --git a/samples/bluetooth/mesh_demo/prj_bbc_microbit.conf b/samples/bluetooth/mesh_demo/prj_bbc_microbit.conf
index 8179de20da..3befdd6218 100644
--- a/samples/bluetooth/mesh_demo/prj_bbc_microbit.conf
+++ b/samples/bluetooth/mesh_demo/prj_bbc_microbit.conf
@@ -1,4 +1,5 @@
 #CONFIG_INIT_STACKS=y
+CONFIG_ISR_STACK_SIZE=768
 CONFIG_MAIN_STACK_SIZE=512
 #CONFIG_SYSTEM_WORKQUEUE_STACK_SIZE=1280
 CONFIG_SYSTEM_WORKQUEUE_STACK_SIZE=2048