diff --git a/Misc/NEWS.d/next/Library/2021-09-11-13-45-47.bpo-45172.T0LUgT.rst b/Misc/NEWS.d/next/Library/2021-09-11-13-45-47.bpo-45172.T0LUgT.rst
new file mode 100644
index 00000000000000..6d5344c531c062
--- /dev/null
+++ b/Misc/NEWS.d/next/Library/2021-09-11-13-45-47.bpo-45172.T0LUgT.rst
@@ -0,0 +1 @@
+Adds ``CAN_RAW_ERR_FILTER`` protocol constant for NetBSD to :mod:`socket`.
diff --git a/Modules/socketmodule.c b/Modules/socketmodule.c
index f376513fead1b8..3a9cdd77c59d5e 100644
--- a/Modules/socketmodule.c
+++ b/Modules/socketmodule.c
@@ -7761,6 +7761,9 @@ PyInit__socket(void)
     PyModule_AddIntMacro(m, CAN_RAW_LOOPBACK);
     PyModule_AddIntMacro(m, CAN_RAW_RECV_OWN_MSGS);
 #endif
+#if defined(CAN_RAW_ERR_FILTER)
+    PyModule_AddIntMacro(m, CAN_RAW_ERR_FILTER);
+#endif
 #ifdef HAVE_LINUX_CAN_RAW_FD_FRAMES
     PyModule_AddIntMacro(m, CAN_RAW_FD_FRAMES);
 #endif
diff --git a/Modules/socketmodule.h b/Modules/socketmodule.h
index 1b35b11cdee6af..7d9870b00e633f 100644
--- a/Modules/socketmodule.h
+++ b/Modules/socketmodule.h
@@ -148,6 +148,10 @@ typedef int socklen_t;
 #include <linux/can/j1939.h>
 #endif
 
+#ifdef HAVE_NETCAN_CAN_H
+#include <netcan/can.h>
+#endif
+
 #ifdef HAVE_SYS_SYS_DOMAIN_H
 #include <sys/sys_domain.h>
 #endif