diff --git a/library/core/src/char/methods.rs b/library/core/src/char/methods.rs
index 02cc0f9d770..6e79e79c143 100644
--- a/library/core/src/char/methods.rs
+++ b/library/core/src/char/methods.rs
@@ -775,13 +775,12 @@ impl char {
     /// In a const context:
     ///
     /// ```
-    /// #![feature(const_unicode_case_lookup)]
     /// const CAPITAL_DELTA_IS_LOWERCASE: bool = 'Δ'.is_lowercase();
     /// assert!(!CAPITAL_DELTA_IS_LOWERCASE);
     /// ```
     #[must_use]
     #[stable(feature = "rust1", since = "1.0.0")]
-    #[rustc_const_unstable(feature = "const_unicode_case_lookup", issue = "101400")]
+    #[rustc_const_stable(feature = "const_unicode_case_lookup", since = "1.84.0")]
     #[inline]
     pub const fn is_lowercase(self) -> bool {
         match self {
@@ -817,13 +816,12 @@ impl char {
     /// In a const context:
     ///
     /// ```
-    /// #![feature(const_unicode_case_lookup)]
     /// const CAPITAL_DELTA_IS_UPPERCASE: bool = 'Δ'.is_uppercase();
     /// assert!(CAPITAL_DELTA_IS_UPPERCASE);
     /// ```
     #[must_use]
     #[stable(feature = "rust1", since = "1.0.0")]
-    #[rustc_const_unstable(feature = "const_unicode_case_lookup", issue = "101400")]
+    #[rustc_const_stable(feature = "const_unicode_case_lookup", since = "1.84.0")]
     #[inline]
     pub const fn is_uppercase(self) -> bool {
         match self {
diff --git a/library/core/src/lib.rs b/library/core/src/lib.rs
index 2f4f33dcc85..1cc353befb8 100644
--- a/library/core/src/lib.rs
+++ b/library/core/src/lib.rs
@@ -134,7 +134,6 @@
 #![feature(const_type_name)]
 #![feature(const_typed_swap)]
 #![feature(const_ub_checks)]
-#![feature(const_unicode_case_lookup)]
 #![feature(core_intrinsics)]
 #![feature(coverage_attribute)]
 #![feature(do_not_recommend)]
diff --git a/library/core/src/unicode/unicode_data.rs b/library/core/src/unicode/unicode_data.rs
index 4655d35e9c4..7f4826402eb 100644
--- a/library/core/src/unicode/unicode_data.rs
+++ b/library/core/src/unicode/unicode_data.rs
@@ -1,6 +1,7 @@
 ///! This file is generated by `./x run src/tools/unicode-table-generator`; do not edit manually!
 
 #[inline(always)]
+#[cfg_attr(bootstrap, rustc_const_stable(feature = "const_unicode_case_lookup", since = "1.84.0"))]
 const fn bitset_search<
     const N: usize,
     const CHUNK_SIZE: usize,
@@ -423,6 +424,7 @@ pub mod lowercase {
         (5, 187), (6, 78), (7, 132),
     ];
 
+    #[cfg_attr(bootstrap, rustc_const_stable(feature = "const_unicode_case_lookup", since = "1.84.0"))]
     pub const fn lookup(c: char) -> bool {
         super::bitset_search(
             c as u32,
@@ -547,6 +549,7 @@ pub mod uppercase {
         (2, 146), (2, 20), (3, 146), (3, 140), (3, 134), (4, 178), (4, 171),
     ];
 
+    #[cfg_attr(bootstrap, rustc_const_stable(feature = "const_unicode_case_lookup", since = "1.84.0"))]
     pub const fn lookup(c: char) -> bool {
         super::bitset_search(
             c as u32,
diff --git a/src/tools/unicode-table-generator/src/range_search.rs b/src/tools/unicode-table-generator/src/range_search.rs
index 9a51979a2f0..14da876eda7 100644
--- a/src/tools/unicode-table-generator/src/range_search.rs
+++ b/src/tools/unicode-table-generator/src/range_search.rs
@@ -1,4 +1,5 @@
 #[inline(always)]
+#[cfg_attr(bootstrap, rustc_const_stable(feature = "const_unicode_case_lookup", since = "1.84.0"))]
 const fn bitset_search<
     const N: usize,
     const CHUNK_SIZE: usize,
diff --git a/src/tools/unicode-table-generator/src/raw_emitter.rs b/src/tools/unicode-table-generator/src/raw_emitter.rs
index 46010692fe5..dd064c59283 100644
--- a/src/tools/unicode-table-generator/src/raw_emitter.rs
+++ b/src/tools/unicode-table-generator/src/raw_emitter.rs
@@ -97,6 +97,10 @@ impl RawEmitter {
 
         self.blank_line();
 
+        writeln!(
+            &mut self.file,
+            r#"#[cfg_attr(bootstrap, rustc_const_stable(feature = "const_unicode_case_lookup", since = "1.84.0"))]"#
+        ).unwrap();
         writeln!(&mut self.file, "pub const fn lookup(c: char) -> bool {{").unwrap();
         if first_code_point > 0x7f {
             writeln!(&mut self.file, "    (c as u32) >= {first_code_point:#04x} &&").unwrap();