diff --git a/mt7915/mac.h b/mt7915/mac.h
index ccce994d..7a2c740d 100644
--- a/mt7915/mac.h
+++ b/mt7915/mac.h
@@ -280,7 +280,8 @@ enum tx_mcu_port_q_idx {
 #define MT_TX_RATE_MODE			GENMASK(9, 6)
 #define MT_TX_RATE_SU_EXT_TONE		BIT(5)
 #define MT_TX_RATE_DCM			BIT(4)
-#define MT_TX_RATE_IDX			GENMASK(3, 0)
+/* VHT/HE only use bits 0-3 */
+#define MT_TX_RATE_IDX			GENMASK(5, 0)
 
 #define MT_TXP_MAX_BUF_NUM		6