diff --git a/include/mbedtls/cipher.h b/include/mbedtls/cipher.h
index ea0ce98..7f3477a 100644
--- a/include/mbedtls/cipher.h
+++ b/include/mbedtls/cipher.h
@@ -45,7 +45,8 @@
 #define MBEDTLS_CIPHER_MODE_WITH_PADDING
 #endif
 
-#if defined(MBEDTLS_ARC4_C) || defined(MBEDTLS_CIPHER_NULL_CIPHER)
+#if defined(MBEDTLS_ARC4_C) || defined(MBEDTLS_CIPHER_NULL_CIPHER) || \
+    defined(MBEDTLS_CHACHA20_C)
 #define MBEDTLS_CIPHER_MODE_STREAM
 #endif