diff --git a/icu4c/source/common/unicode/casemap.h b/icu4c/source/common/unicode/casemap.h
index 8401867b8ab..e0e4aafcf90 100644
--- a/icu4c/source/common/unicode/casemap.h
+++ b/icu4c/source/common/unicode/casemap.h
@@ -60,8 +60,8 @@ public:
      */
      static int32_t toLower(
             const char *locale, uint32_t options,
-            ConstChar16Ptr src, int32_t srcLength,
-            Char16Ptr dest, int32_t destCapacity, Edits *edits,
+            const char16_t *src, int32_t srcLength,
+            char16_t *dest, int32_t destCapacity, Edits *edits,
             UErrorCode &errorCode);
 
     /**
@@ -94,8 +94,8 @@ public:
      */
     static int32_t toUpper(
             const char *locale, uint32_t options,
-            ConstChar16Ptr src, int32_t srcLength,
-            Char16Ptr dest, int32_t destCapacity, Edits *edits,
+            const char16_t *src, int32_t srcLength,
+            char16_t *dest, int32_t destCapacity, Edits *edits,
             UErrorCode &errorCode);
 
 #if !UCONFIG_NO_BREAK_ITERATION
@@ -141,8 +141,8 @@ public:
      */
     static int32_t toTitle(
             const char *locale, uint32_t options, BreakIterator *iter,
-            ConstChar16Ptr src, int32_t srcLength,
-            Char16Ptr dest, int32_t destCapacity, Edits *edits,
+            const char16_t *src, int32_t srcLength,
+            char16_t *dest, int32_t destCapacity, Edits *edits,
             UErrorCode &errorCode);
 
 #endif  // UCONFIG_NO_BREAK_ITERATION
@@ -181,8 +181,8 @@ public:
      */
     static int32_t fold(
             uint32_t options,
-            ConstChar16Ptr src, int32_t srcLength,
-            Char16Ptr dest, int32_t destCapacity, Edits *edits,
+            const char16_t *src, int32_t srcLength,
+            char16_t *dest, int32_t destCapacity, Edits *edits,
             UErrorCode &errorCode);
 
 private:
diff --git a/icu4c/source/common/ustr_titlecase_brkiter.cpp b/icu4c/source/common/ustr_titlecase_brkiter.cpp
index ac46bc9359f..0b2ba02064b 100644
--- a/icu4c/source/common/ustr_titlecase_brkiter.cpp
+++ b/icu4c/source/common/ustr_titlecase_brkiter.cpp
@@ -66,8 +66,8 @@ U_NAMESPACE_BEGIN
 
 int32_t CaseMap::toTitle(
         const char *locale, uint32_t options, BreakIterator *iter,
-        ConstChar16Ptr src, int32_t srcLength,
-        Char16Ptr dest, int32_t destCapacity, Edits *edits,
+        const UChar *src, int32_t srcLength,
+        UChar *dest, int32_t destCapacity, Edits *edits,
         UErrorCode &errorCode) {
     LocalPointer<BreakIterator> ownedIter;
     if(iter==NULL) {
diff --git a/icu4c/source/common/ustrcase.cpp b/icu4c/source/common/ustrcase.cpp
index d0bdd1511ab..0e38a42e103 100644
--- a/icu4c/source/common/ustrcase.cpp
+++ b/icu4c/source/common/ustrcase.cpp
@@ -1198,8 +1198,8 @@ U_NAMESPACE_BEGIN
 
 int32_t CaseMap::fold(
         uint32_t options,
-        ConstChar16Ptr src, int32_t srcLength,
-        Char16Ptr dest, int32_t destCapacity, Edits *edits,
+        const UChar *src, int32_t srcLength,
+        UChar *dest, int32_t destCapacity, Edits *edits,
         UErrorCode &errorCode) {
     return ustrcase_map(
         UCASE_LOC_ROOT, options, UCASEMAP_BREAK_ITERATOR_NULL
diff --git a/icu4c/source/common/ustrcase_locale.cpp b/icu4c/source/common/ustrcase_locale.cpp
index 0c6d095d367..2ecd24f03ec 100644
--- a/icu4c/source/common/ustrcase_locale.cpp
+++ b/icu4c/source/common/ustrcase_locale.cpp
@@ -69,8 +69,8 @@ U_NAMESPACE_BEGIN
 
 int32_t CaseMap::toLower(
         const char *locale, uint32_t options,
-        ConstChar16Ptr src, int32_t srcLength,
-        Char16Ptr dest, int32_t destCapacity, Edits *edits,
+        const UChar *src, int32_t srcLength,
+        UChar *dest, int32_t destCapacity, Edits *edits,
         UErrorCode &errorCode) {
     return ustrcase_map(
         ustrcase_getCaseLocale(locale), options, UCASEMAP_BREAK_ITERATOR_NULL
@@ -81,8 +81,8 @@ int32_t CaseMap::toLower(
 
 int32_t CaseMap::toUpper(
         const char *locale, uint32_t options,
-        ConstChar16Ptr src, int32_t srcLength,
-        Char16Ptr dest, int32_t destCapacity, Edits *edits,
+        const UChar *src, int32_t srcLength,
+        UChar *dest, int32_t destCapacity, Edits *edits,
         UErrorCode &errorCode) {
     return ustrcase_map(
         ustrcase_getCaseLocale(locale), options, UCASEMAP_BREAK_ITERATOR_NULL