diff --git a/icu4c/source/i18n/unicode/coll.h b/icu4c/source/i18n/unicode/coll.h
index 0ea37dfcc0..3b94608871 100644
--- a/icu4c/source/i18n/unicode/coll.h
+++ b/icu4c/source/i18n/unicode/coll.h
@@ -52,6 +52,9 @@
 
 U_NAMESPACE_BEGIN
 
+/**
+* @stable
+*/
 class CollationKey;
 
 /**
diff --git a/icu4c/source/i18n/unicode/search.h b/icu4c/source/i18n/unicode/search.h
index f52f098d6a..e75ded699e 100644
--- a/icu4c/source/i18n/unicode/search.h
+++ b/icu4c/source/i18n/unicode/search.h
@@ -17,7 +17,13 @@
 #include "unicode/brkiter.h"
 #include "unicode/usearch.h"
 
+/**
+* @stable
+*/
 struct USearch;
+/**
+* @stable
+*/
 typedef struct USearch USearch;
 
 U_NAMESPACE_BEGIN
diff --git a/icu4c/source/i18n/unicode/tblcoll.h b/icu4c/source/i18n/unicode/tblcoll.h
index b13c038637..9e5b68286e 100644
--- a/icu4c/source/i18n/unicode/tblcoll.h
+++ b/icu4c/source/i18n/unicode/tblcoll.h
@@ -60,7 +60,13 @@
 
 U_NAMESPACE_BEGIN
 
+/**
+* @stable
+*/
 class StringSearch;
+/**
+* @stable
+*/
 class CollationElementIterator;
 
 /**