diff --git a/include/zephyr/arch/riscv/reg.h b/include/zephyr/arch/riscv/reg.h
index 6d3b2d88b1755..2c0650f0498f1 100644
--- a/include/zephyr/arch/riscv/reg.h
+++ b/include/zephyr/arch/riscv/reg.h
@@ -7,6 +7,8 @@
 #ifndef ZEPHYR_INCLUDE_ZEPHYR_ARCH_RISCV_REG_H_
 #define ZEPHYR_INCLUDE_ZEPHYR_ARCH_RISCV_REG_H_
 
+#include <zephyr/sys/util.h>
+
 #define reg_read(reg)                                                                              \
 	({                                                                                         \
 		register unsigned long __rv;                                                       \