diff --git a/sys/net/gnrc/routing/ipv6_auto_subnets/gnrc_ipv6_auto_subnets.c b/sys/net/gnrc/routing/ipv6_auto_subnets/gnrc_ipv6_auto_subnets.c
index b0b9e0cd04..75b367910c 100644
--- a/sys/net/gnrc/routing/ipv6_auto_subnets/gnrc_ipv6_auto_subnets.c
+++ b/sys/net/gnrc/routing/ipv6_auto_subnets/gnrc_ipv6_auto_subnets.c
@@ -89,6 +89,7 @@
  * @author  Benjamin Valentin <benjamin.valentin@ml-pa.com>
  */
 
+#include "compiler_hints.h"
 #include "net/gnrc/ipv6.h"
 #include "net/gnrc/netif.h"
 #include "net/gnrc/netif/hdr.h"
@@ -141,6 +142,14 @@
 #define CONFIG_GNRC_IPV6_AUTO_SUBNETS_PREFIX_FIX_LEN (0)
 #endif
 
+/**
+ * @brief   Minimal length of a new prefix.
+ *          e.g. Linux will only accept /64 prefixes for SLAAC
+ */
+#ifndef CONFIG_GNRC_IPV6_AUTO_SUBNETS_PREFIX_MIN_LEN
+#define CONFIG_GNRC_IPV6_AUTO_SUBNETS_PREFIX_MIN_LEN (0)
+#endif
+
 /**
  * @brief Number of subnets that can be configured.
  *
@@ -369,6 +378,10 @@ static void _configure_subnets(uint8_t subnets, uint8_t start_idx, gnrc_netif_t
         return;
     }
 
+    if (new_prefix_len < may_be_zero(CONFIG_GNRC_IPV6_AUTO_SUBNETS_PREFIX_MIN_LEN)) {
+        new_prefix_len = CONFIG_GNRC_IPV6_AUTO_SUBNETS_PREFIX_MIN_LEN;
+    }
+
     while ((downstream = gnrc_netif_iter(downstream))) {
         gnrc_pktsnip_t *tmp;
         ipv6_addr_t new_prefix;