diff --git a/icu4c/source/i18n/translit.cpp b/icu4c/source/i18n/translit.cpp
index 61cbe1b46fe..62102684675 100644
--- a/icu4c/source/i18n/translit.cpp
+++ b/icu4c/source/i18n/translit.cpp
@@ -1467,6 +1467,8 @@ const UnicodeString& Transliterator::getAvailableID(int32_t index) {
 /**
  * Method for subclasses to use to obtain a character in the given
  * string, with filtering.
+ * @deprecated the new architecture provides filtering at the top
+ * level.  This method will be removed Dec 31 2001.
  */
 UChar Transliterator::filteredCharAt(const Replaceable& text, int32_t i) const {
     UChar c;
diff --git a/icu4c/source/i18n/unicode/translit.h b/icu4c/source/i18n/unicode/translit.h
index fa04bca1fb0..6bce71a093f 100644
--- a/icu4c/source/i18n/unicode/translit.h
+++ b/icu4c/source/i18n/unicode/translit.h
@@ -969,6 +969,8 @@ protected:
      * Method for subclasses to use to obtain a character in the given
      * string, with filtering.  If the character at the given offset
      * is excluded by this transliterator's filter, then U+FFFE is returned.
+     * @deprecated the new architecture provides filtering at the top
+     * level.  This method will be removed Dec 31 2001.
      */
     UChar filteredCharAt(const Replaceable& text, int32_t i) const;