diff --git a/src/env_universal_common.rs b/src/env_universal_common.rs
index 2f9f98423..497956de3 100644
--- a/src/env_universal_common.rs
+++ b/src/env_universal_common.rs
@@ -10,7 +10,7 @@ use crate::fds::{open_cloexec, wopen_cloexec};
 use crate::flog::{FLOG, FLOGF};
 use crate::path::path_get_config;
 use crate::path::{path_get_config_remoteness, DirRemoteness};
-use crate::wchar::prelude::*;
+use crate::wchar::{decode_byte_from_char, prelude::*};
 use crate::wcstringutil::{join_strings, split_string, string_suffixes_string, LineIterator};
 use crate::wutil::{
     file_id_for_fd, file_id_for_path, file_id_for_path_narrow, wdirname, wrealpath, wrename, wstat,
@@ -904,6 +904,8 @@ fn full_escape(input: &wstr) -> WString {
             out.push(c);
         } else if c.is_ascii() {
             sprintf!(=> &mut out, "\\x%.2x", u32::from(c));
+        } else if let Some(encoded_byte) = decode_byte_from_char(c) {
+            sprintf!(=> &mut out, "\\x%.2x", u32::from(encoded_byte));
         } else if u32::from(c) < 65536 {
             sprintf!(=> &mut out, "\\u%.4x", u32::from(c));
         } else {
diff --git a/src/tests/env_universal_common.rs b/src/tests/env_universal_common.rs
index 1ecfc25d2..13aee0607 100644
--- a/src/tests/env_universal_common.rs
+++ b/src/tests/env_universal_common.rs
@@ -1,5 +1,7 @@
+use crate::common::char_offset;
 use crate::common::wcs2osstring;
 use crate::common::ScopeGuard;
+use crate::common::ENCODE_DIRECT_BASE;
 use crate::env::{EnvVar, EnvVarFlags, VarTable};
 use crate::env_universal_common::{CallbackDataList, EnvUniversal, UvarFormat};
 use crate::parser::Parser;
@@ -109,6 +111,13 @@ fn test_universal_output() {
             flag_pathvar,
         ),
     );
+    vars.insert(
+        L!("varF").to_owned(),
+        EnvVar::new_vec(
+            vec![WString::from_chars([char_offset(ENCODE_DIRECT_BASE, 0xfc)])],
+            EnvVarFlags::empty(),
+        ),
+    );
 
     let text = EnvUniversal::serialize_with_vars(&vars);
     let expected = concat!(
@@ -119,6 +128,7 @@ fn test_universal_output() {
         "SETUVAR varC:ValC1\n",
         "SETUVAR --export --path varD:ValD1\n",
         "SETUVAR --path varE:ValE1\\x1eValE2\n",
+        "SETUVAR varF:\\xfc\n",
     )
     .as_bytes();
     assert_eq!(text, expected);