diff --git a/libguile/finalizers.c b/libguile/finalizers.c
index 8b680d68c..d486ef842 100644
--- a/libguile/finalizers.c
+++ b/libguile/finalizers.c
@@ -165,6 +165,12 @@ smob_finalizer_trampoline (void *ptr, void *data)
   scm_i_finalize_smob (SCM_I_CURRENT_THREAD, PTR2SCM (ptr));
 }
 
+static void
+port_finalizer_trampoline (void *ptr, void *data)
+{
+  scm_i_finalize_port (SCM_I_CURRENT_THREAD, PTR2SCM (ptr));
+}
+
 SCM
 scm_i_add_struct_finalizer (struct scm_thread *thread, SCM obj)
 {
@@ -185,6 +191,16 @@ scm_i_add_smob_finalizer (struct scm_thread *thread, SCM obj)
   return SCM_UNSPECIFIED;
 }
 
+SCM
+scm_i_add_port_finalizer (struct scm_thread *thread, SCM obj)
+{
+  if (!SCM_PORTP (obj))
+    abort ();
+
+  scm_i_set_finalizer (SCM2PTR (obj), port_finalizer_trampoline, NULL);
+  return SCM_UNSPECIFIED;
+}
+
 static void
 invoke_finalizer (void *obj, void *data)
 {
diff --git a/libguile/finalizers.h b/libguile/finalizers.h
index 6934a21d7..8c29fdb8a 100644
--- a/libguile/finalizers.h
+++ b/libguile/finalizers.h
@@ -39,6 +39,8 @@ SCM_INTERNAL SCM scm_i_add_struct_finalizer (struct scm_thread *thread,
                                              SCM obj);
 SCM_INTERNAL SCM scm_i_add_smob_finalizer (struct scm_thread *thread,
                                            SCM obj);
+SCM_INTERNAL SCM scm_i_add_port_finalizer (struct scm_thread *thread,
+                                           SCM obj);
 
 SCM_INTERNAL void scm_i_finalizer_pre_fork (void);
 
diff --git a/libguile/ports.c b/libguile/ports.c
index 764fa9376..e979edada 100644
--- a/libguile/ports.c
+++ b/libguile/ports.c
@@ -1,4 +1,4 @@
-/* Copyright 1995-2001,2003-2004,2006-2019,2021,2024
+/* Copyright 1995-2001,2003-2004,2006-2019,2021,2024,2025
      Free Software Foundation, Inc.
 
    This file is part of Guile.
@@ -713,27 +713,16 @@ SCM scm_i_port_weak_set;
 /* Port finalization.  */
 
 static SCM close_port (SCM, int);
-
-static SCM
-do_close (void *data)
+void
+scm_i_finalize_port (struct scm_thread *thread, SCM port)
 {
-  return close_port (SCM_PACK_POINTER (data), 0);
-}
-
-/* Finalize the object (a port) pointed to by PTR.  */
-static void
-finalize_port (void *ptr, void *data)
-{
-  SCM port = SCM_PACK_POINTER (ptr);
-
   if (!SCM_PORTP (port))
     abort ();
 
   if (SCM_OPENP (port))
     {
       SCM_SET_PORT_FINALIZING (port);
-      scm_internal_catch (SCM_BOOL_T, do_close, ptr,
-                          scm_handle_by_message_noexit, NULL);
+      close_port (port, 0);
       scm_gc_ports_collected++;
     }
 }
@@ -808,7 +797,7 @@ scm_c_make_port_with_encoding (scm_t_port_type *ptob, unsigned long mode_bits,
 
   if (SCM_PORT_TYPE (ret)->flags & SCM_PORT_TYPE_NEEDS_CLOSE_ON_GC)
     {
-      scm_i_set_finalizer (SCM2PTR (ret), finalize_port, NULL);
+      scm_i_add_port_finalizer (SCM_I_CURRENT_THREAD, ret);
       scm_weak_set_add_x (scm_i_port_weak_set, ret);
     }
 
@@ -1161,7 +1150,7 @@ prepare_iconv_descriptors (SCM port, SCM precise_encoding)
   pt->output_cd = output_cd;
 
   /* Make sure this port has a finalizer.  */
-  scm_i_set_finalizer (SCM2PTR (port), finalize_port, NULL);
+  scm_i_add_port_finalizer (SCM_I_CURRENT_THREAD, port);
 
   return;
 
diff --git a/libguile/ports.h b/libguile/ports.h
index d481c2967..055e5b6b9 100644
--- a/libguile/ports.h
+++ b/libguile/ports.h
@@ -1,7 +1,7 @@
 #ifndef SCM_PORTS_H
 #define SCM_PORTS_H
 
-/* Copyright 1995-2001,2003-2004,2006,2008-2014,2018
+/* Copyright 1995-2001,2003-2004,2006,2008-2014,2018,2025
      Free Software Foundation, Inc.
 
    This file is part of Guile.
@@ -164,6 +164,7 @@ SCM_API SCM scm_c_make_port_with_encoding (scm_t_port_type *ptob,
                                            scm_t_bits stream);
 SCM_API SCM scm_c_make_port (scm_t_port_type *ptob, unsigned long mode_bits,
                              scm_t_bits stream);
+SCM_INTERNAL void scm_i_finalize_port (struct scm_thread *thread, SCM obj);
 
 /* Predicates.  */
 SCM_API SCM scm_port_p (SCM x);