diff --git a/nimble/transport/ram/syscfg.yml b/nimble/transport/ram/syscfg.yml
index 0323ace6c..60060771a 100644
--- a/nimble/transport/ram/syscfg.yml
+++ b/nimble/transport/ram/syscfg.yml
@@ -40,3 +40,6 @@ syscfg.defs:
             This is the maximum size of the data portion of HCI ACL data
             packets. It does not include the HCI data header (of 4 bytes).
         value: 255
+
+syscfg.vals.BLE_EXT_ADV:
+    BLE_HCI_EVT_BUF_SIZE: 274
diff --git a/nimble/transport/socket/syscfg.yml b/nimble/transport/socket/syscfg.yml
index 477d49351..e2354c5a9 100644
--- a/nimble/transport/socket/syscfg.yml
+++ b/nimble/transport/socket/syscfg.yml
@@ -64,3 +64,5 @@ syscfg.defs:
         description: 'linux kernel device'
         value: 0
 
+syscfg.vals.BLE_EXT_ADV:
+    BLE_HCI_EVT_BUF_SIZE: 274
diff --git a/nimble/transport/uart/syscfg.yml b/nimble/transport/uart/syscfg.yml
index 81b47f373..0ffa1da35 100644
--- a/nimble/transport/uart/syscfg.yml
+++ b/nimble/transport/uart/syscfg.yml
@@ -66,3 +66,6 @@ syscfg.defs:
     BLE_HCI_UART_FLOW_CTRL:
         description: 'Flow control used for HCI uart interface'
         value:       HAL_UART_FLOW_CTL_RTS_CTS
+
+syscfg.vals.BLE_EXT_ADV:
+    BLE_HCI_EVT_BUF_SIZE: 274