diff --git a/Kbuild b/Kbuild
index 073a2b1b6db5..0f471723f60e 100644
--- a/Kbuild
+++ b/Kbuild
@@ -3309,6 +3309,10 @@ cppflags-y += -DDP_MON_RSSI_IN_DBM
 cppflags-y += -DSYSTEM_PM_CHECK
 endif
 
+ifeq ($(CONFIG_TX_AGGREGATION_SIZE_ENABLE), y)
+cppflags-y += -DTX_AGGREGATION_SIZE_ENABLE
+endif
+
 # Enable Low latency optimisation mode
 cppflags-$(CONFIG_WLAN_FEATURE_LL_MODE) += -DWLAN_FEATURE_LL_MODE