diff --git a/icu4c/source/common/uenum.c b/icu4c/source/common/uenum.c
index 0ec065a8e14..dbf1d709040 100644
--- a/icu4c/source/common/uenum.c
+++ b/icu4c/source/common/uenum.c
@@ -14,6 +14,7 @@
 *   created by: Vladimir Weinstein
 */
 
+#include "unicode/putil.h"
 #include "uenumimp.h"
 #include "cmemory.h"
 
diff --git a/icu4c/source/common/unames.c b/icu4c/source/common/unames.c
index 43b9ae05d01..1ff98ec7f79 100644
--- a/icu4c/source/common/unames.c
+++ b/icu4c/source/common/unames.c
@@ -15,6 +15,7 @@
 */
 
 #include "unicode/utypes.h"
+#include "unicode/putil.h"
 #include "unicode/uchar.h"
 #include "unicode/udata.h"
 #include "ustr_imp.h"
diff --git a/icu4c/source/common/unicode/putil.h b/icu4c/source/common/unicode/putil.h
index 0adb59da70a..685df530ef3 100644
--- a/icu4c/source/common/unicode/putil.h
+++ b/icu4c/source/common/unicode/putil.h
@@ -134,4 +134,47 @@ U_INTERNAL const char*  U_EXPORT2 uprv_getDefaultLocaleID(void);
 #   define U_PATH_SEP_STRING ":"
 #endif
 
+/**
+ * Convert char characters to UChar characters.
+ * This utility function is useful only for "invariant characters"
+ * that are encoded in the platform default encoding.
+ * They are a small, constant subset of the encoding and include
+ * just the latin letters, digits, and some punctuation.
+ * For details, see U_CHARSET_FAMILY.
+ *
+ * @param cs Input string, points to <code>length</code>
+ *           character bytes from a subset of the platform encoding.
+ * @param us Output string, points to memory for <code>length</code>
+ *           Unicode characters.
+ * @param length The number of characters to convert; this may
+ *               include the terminating <code>NUL</code>.
+ *
+ * @see U_CHARSET_FAMILY
+ * @stable ICU 2.0
+ */
+U_STABLE void U_EXPORT2
+u_charsToUChars(const char *cs, UChar *us, int32_t length);
+
+/**
+ * Convert UChar characters to char characters.
+ * This utility function is useful only for "invariant characters"
+ * that can be encoded in the platform default encoding.
+ * They are a small, constant subset of the encoding and include
+ * just the latin letters, digits, and some punctuation.
+ * For details, see U_CHARSET_FAMILY.
+ *
+ * @param us Input string, points to <code>length</code>
+ *           Unicode characters that can be encoded with the
+ *           codepage-invariant subset of the platform encoding.
+ * @param cs Output string, points to memory for <code>length</code>
+ *           character bytes.
+ * @param length The number of characters to convert; this may
+ *               include the terminating <code>NUL</code>.
+ *
+ * @see U_CHARSET_FAMILY
+ * @stable ICU 2.0
+ */
+U_STABLE void U_EXPORT2
+u_UCharsToChars(const UChar *us, char *cs, int32_t length);
+
 #endif
diff --git a/icu4c/source/common/unicode/utypes.h b/icu4c/source/common/unicode/utypes.h
index 4d778aa2df8..77513662d2e 100644
--- a/icu4c/source/common/unicode/utypes.h
+++ b/icu4c/source/common/unicode/utypes.h
@@ -124,49 +124,6 @@
 #   define U_CHARSET_FAMILY 0
 #endif
 
-/**
- * Convert char characters to UChar characters.
- * This utility function is useful only for "invariant characters"
- * that are encoded in the platform default encoding.
- * They are a small, constant subset of the encoding and include
- * just the latin letters, digits, and some punctuation.
- * For details, see U_CHARSET_FAMILY.
- *
- * @param cs Input string, points to <code>length</code>
- *           character bytes from a subset of the platform encoding.
- * @param us Output string, points to memory for <code>length</code>
- *           Unicode characters.
- * @param length The number of characters to convert; this may
- *               include the terminating <code>NUL</code>.
- *
- * @see U_CHARSET_FAMILY
- * @stable ICU 2.0
- */
-U_STABLE void U_EXPORT2
-u_charsToUChars(const char *cs, UChar *us, int32_t length);
-
-/**
- * Convert UChar characters to char characters.
- * This utility function is useful only for "invariant characters"
- * that can be encoded in the platform default encoding.
- * They are a small, constant subset of the encoding and include
- * just the latin letters, digits, and some punctuation.
- * For details, see U_CHARSET_FAMILY.
- *
- * @param us Input string, points to <code>length</code>
- *           Unicode characters that can be encoded with the
- *           codepage-invariant subset of the platform encoding.
- * @param cs Output string, points to memory for <code>length</code>
- *           character bytes.
- * @param length The number of characters to convert; this may
- *               include the terminating <code>NUL</code>.
- *
- * @see U_CHARSET_FAMILY
- * @stable ICU 2.0
- */
-U_STABLE void U_EXPORT2
-u_UCharsToChars(const UChar *us, char *cs, int32_t length);
-
 /*===========================================================================*/
 /* ICUDATA naming scheme                                                     */
 /*===========================================================================*/
@@ -704,44 +661,44 @@ typedef enum UErrorCode {
     /*
      * The error codes in the range 0x10300-0x103ff are reserved for regular expression related errrs
      */
-     U_REGEX_ERROR_START=0x10300,          /**< Start of codes indicating Regexp failures          */
-     U_REGEX_INTERNAL_ERROR,               /**< An internal error (bug) was detected.              */
-     U_REGEX_RULE_SYNTAX,                  /**< Syntax error in regexp pattern.                    */
-     U_REGEX_INVALID_STATE,                /**< RegexMatcher in invalid state for requested operation */
-     U_REGEX_BAD_ESCAPE_SEQUENCE,          /**< Unrecognized backslash escape sequence in pattern  */
-     U_REGEX_PROPERTY_SYNTAX,              /**< Incorrect Unicode property                         */
-     U_REGEX_UNIMPLEMENTED,                /**< Use of regexp feature that is not yet implemented. */
-     U_REGEX_MISMATCHED_PAREN,             /**< Incorrectly nested parentheses in regexp pattern.  */
-     U_REGEX_NUMBER_TOO_BIG,               /**< Decimal number is too large.                       */
-     U_REGEX_BAD_INTERVAL,                 /**< Error in {min,max} interval                        */
-     U_REGEX_MAX_LT_MIN,                   /**< In {min,max}, max is less than min.                */
-     U_REGEX_INVALID_BACK_REF,             /**< Back-reference to a non-existent capture group.    */
-     U_REGEX_INVALID_FLAG,                 /**< Invalid value for match mode flags.                */
-     U_REGEX_LOOK_BEHIND_LIMIT,            /**< Look-Behind pattern matches must have a bounded maximum length.    */
-     U_REGEX_SET_CONTAINS_STRING,          /**< Regexps cannot have UnicodeSets containing strings.*/
-     U_REGEX_ERROR_LIMIT,                  /**< This must always be the last value to indicate the limit for regexp errors */
+    U_REGEX_ERROR_START=0x10300,          /**< Start of codes indicating Regexp failures          */
+    U_REGEX_INTERNAL_ERROR,               /**< An internal error (bug) was detected.              */
+    U_REGEX_RULE_SYNTAX,                  /**< Syntax error in regexp pattern.                    */
+    U_REGEX_INVALID_STATE,                /**< RegexMatcher in invalid state for requested operation */
+    U_REGEX_BAD_ESCAPE_SEQUENCE,          /**< Unrecognized backslash escape sequence in pattern  */
+    U_REGEX_PROPERTY_SYNTAX,              /**< Incorrect Unicode property                         */
+    U_REGEX_UNIMPLEMENTED,                /**< Use of regexp feature that is not yet implemented. */
+    U_REGEX_MISMATCHED_PAREN,             /**< Incorrectly nested parentheses in regexp pattern.  */
+    U_REGEX_NUMBER_TOO_BIG,               /**< Decimal number is too large.                       */
+    U_REGEX_BAD_INTERVAL,                 /**< Error in {min,max} interval                        */
+    U_REGEX_MAX_LT_MIN,                   /**< In {min,max}, max is less than min.                */
+    U_REGEX_INVALID_BACK_REF,             /**< Back-reference to a non-existent capture group.    */
+    U_REGEX_INVALID_FLAG,                 /**< Invalid value for match mode flags.                */
+    U_REGEX_LOOK_BEHIND_LIMIT,            /**< Look-Behind pattern matches must have a bounded maximum length.    */
+    U_REGEX_SET_CONTAINS_STRING,          /**< Regexps cannot have UnicodeSets containing strings.*/
+    U_REGEX_ERROR_LIMIT,                  /**< This must always be the last value to indicate the limit for regexp errors */
 
-     /*
-      * The error code in the range 0x10400-0x104ff are reserved for IDNA related error codes
-      */
-      U_IDNA_ERROR_START=0x10400,
-      U_IDNA_PROHIBITED_ERROR,
-      U_IDNA_UNASSIGNED_ERROR,
-      U_IDNA_CHECK_BIDI_ERROR,
-      U_IDNA_STD3_ASCII_RULES_ERROR,
-      U_IDNA_ACE_PREFIX_ERROR,
-      U_IDNA_VERIFICATION_ERROR,
-      U_IDNA_LABEL_TOO_LONG_ERROR,
-      U_IDNA_ERROR_LIMIT,
-      /*
-       * Aliases for StringPrep
-       */
-      U_STRINGPREP_PROHIBITED_ERROR = U_IDNA_PROHIBITED_ERROR,
-      U_STRINGPREP_UNASSIGNED_ERROR = U_IDNA_UNASSIGNED_ERROR,
-      U_STRINGPREP_CHECK_BIDI_ERROR = U_IDNA_CHECK_BIDI_ERROR,
+    /*
+     * The error code in the range 0x10400-0x104ff are reserved for IDNA related error codes
+     */
+    U_IDNA_ERROR_START=0x10400,
+    U_IDNA_PROHIBITED_ERROR,
+    U_IDNA_UNASSIGNED_ERROR,
+    U_IDNA_CHECK_BIDI_ERROR,
+    U_IDNA_STD3_ASCII_RULES_ERROR,
+    U_IDNA_ACE_PREFIX_ERROR,
+    U_IDNA_VERIFICATION_ERROR,
+    U_IDNA_LABEL_TOO_LONG_ERROR,
+    U_IDNA_ERROR_LIMIT,
+    /*
+     * Aliases for StringPrep
+     */
+    U_STRINGPREP_PROHIBITED_ERROR = U_IDNA_PROHIBITED_ERROR,
+    U_STRINGPREP_UNASSIGNED_ERROR = U_IDNA_UNASSIGNED_ERROR,
+    U_STRINGPREP_CHECK_BIDI_ERROR = U_IDNA_CHECK_BIDI_ERROR,
 
 
-      U_ERROR_LIMIT=U_IDNA_ERROR_LIMIT      /**< This must always be the last value to indicate the limit for UErrorCode (last error code +1) */
+    U_ERROR_LIMIT=U_IDNA_ERROR_LIMIT      /**< This must always be the last value to indicate the limit for UErrorCode (last error code +1) */
 } UErrorCode;
 
 /* Use the following to determine if an UErrorCode represents */
diff --git a/icu4c/source/common/ures_cnv.c b/icu4c/source/common/ures_cnv.c
index e7c5606f6b6..9326ef127be 100644
--- a/icu4c/source/common/ures_cnv.c
+++ b/icu4c/source/common/ures_cnv.c
@@ -17,6 +17,7 @@
 */
 
 #include "unicode/utypes.h"
+#include "unicode/putil.h"
 #include "unicode/ustring.h"
 #include "unicode/ucnv.h"
 #include "unicode/ures.h"
diff --git a/icu4c/source/common/uscript.c b/icu4c/source/common/uscript.c
index 61ea2cd223f..797d15155c7 100644
--- a/icu4c/source/common/uscript.c
+++ b/icu4c/source/common/uscript.c
@@ -16,6 +16,7 @@
 #include "unicode/uscript.h"
 #include "unicode/ures.h"
 #include "unicode/uchar.h"
+#include "unicode/putil.h"
 #include "uprops.h"
 #include "cmemory.h"
 #include "cstring.h"
diff --git a/icu4c/source/common/ustrenum.cpp b/icu4c/source/common/ustrenum.cpp
index 3ddf3476849..dfc1ba1fc11 100644
--- a/icu4c/source/common/ustrenum.cpp
+++ b/icu4c/source/common/ustrenum.cpp
@@ -10,6 +10,7 @@
 */
 #include "unicode/ustring.h"
 #include "unicode/strenum.h"
+#include "unicode/putil.h"
 #include "uenumimp.h"
 #include "ustrenum.h"
 #include "cstring.h"
diff --git a/icu4c/source/common/ustring.c b/icu4c/source/common/ustring.c
index 9d1a60ead99..8c49959c8c1 100644
--- a/icu4c/source/common/ustring.c
+++ b/icu4c/source/common/ustring.c
@@ -16,6 +16,7 @@
 */
 
 #include "unicode/utypes.h"
+#include "unicode/putil.h"
 #include "unicode/ustring.h"
 #include "cstring.h"
 #include "cwchar.h"
diff --git a/icu4c/source/extra/uconv/uwmsg.c b/icu4c/source/extra/uconv/uwmsg.c
index e1c065c9e24..61e6c463719 100644
--- a/icu4c/source/extra/uconv/uwmsg.c
+++ b/icu4c/source/extra/uconv/uwmsg.c
@@ -18,6 +18,7 @@
 #include "unicode/umsg.h"
 #include "unicode/uwmsg.h"
 #include "unicode/ures.h"
+#include "unicode/putil.h"
 #include "cstring.h"
 
 #include <stdlib.h>
diff --git a/icu4c/source/io/sprintf.c b/icu4c/source/io/sprintf.c
index 87b533275dd..0d90b561bef 100644
--- a/icu4c/source/io/sprintf.c
+++ b/icu4c/source/io/sprintf.c
@@ -24,6 +24,7 @@
 
 #include "unicode/ustdio.h"
 #include "unicode/ustring.h"
+#include "unicode/putil.h"
 
 #include "uprintf.h"
 #include "locbund.h"
diff --git a/icu4c/source/io/sscanf.c b/icu4c/source/io/sscanf.c
index a8d564ddf38..eb0bedfb84e 100644
--- a/icu4c/source/io/sscanf.c
+++ b/icu4c/source/io/sscanf.c
@@ -19,6 +19,7 @@
 
 #if !UCONFIG_NO_FORMATTING
 
+#include "unicode/putil.h"
 #include "unicode/ustdio.h"
 #include "unicode/ustring.h"
 #include "uscanf.h"
diff --git a/icu4c/source/io/uprintf.c b/icu4c/source/io/uprintf.c
index 2f1a376b9d6..d95c02c671c 100644
--- a/icu4c/source/io/uprintf.c
+++ b/icu4c/source/io/uprintf.c
@@ -26,6 +26,7 @@
 #include "unicode/ustring.h"
 #include "unicode/unum.h"
 #include "unicode/udat.h"
+#include "unicode/putil.h"
 
 #include "uprintf.h"
 #include "ufile.h"
diff --git a/icu4c/source/io/uscanf.c b/icu4c/source/io/uscanf.c
index b6befe3eef8..5743f651991 100644
--- a/icu4c/source/io/uscanf.c
+++ b/icu4c/source/io/uscanf.c
@@ -20,6 +20,7 @@
 
 #if !UCONFIG_NO_FORMATTING
 
+#include "unicode/putil.h"
 #include "unicode/ustdio.h"
 #include "unicode/ustring.h"
 #include "uscanf.h"
diff --git a/icu4c/source/test/cintltst/cintltst.h b/icu4c/source/test/cintltst/cintltst.h
index 6f265e193ca..199496e0d3c 100644
--- a/icu4c/source/test/cintltst/cintltst.h
+++ b/icu4c/source/test/cintltst/cintltst.h
@@ -20,6 +20,7 @@ The main root for C API tests
 #define _CINTLTST
 
 #include "unicode/utypes.h"
+#include "unicode/putil.h"
 #include "unicode/ctest.h"
 
 #ifndef U_USE_DEPRECATED_API
diff --git a/icu4c/source/test/intltest/testidna.cpp b/icu4c/source/test/intltest/testidna.cpp
index 626cfbe2b0b..6c9498538d6 100644
--- a/icu4c/source/test/intltest/testidna.cpp
+++ b/icu4c/source/test/intltest/testidna.cpp
@@ -28,6 +28,7 @@
 #include "testidna.h"
 #include "idnaref.h"
 #include "nptrans.h"
+#include "unicode/putil.h"
 
 static UChar unicodeIn[][41] ={
     { 
diff --git a/icu4c/source/tools/genrb/ustr.c b/icu4c/source/tools/genrb/ustr.c
index ff1344f3e8a..da0e40e7667 100644
--- a/icu4c/source/tools/genrb/ustr.c
+++ b/icu4c/source/tools/genrb/ustr.c
@@ -19,6 +19,7 @@
 #include "cmemory.h"
 #include "cstring.h"
 #include "unicode/ustring.h"
+#include "unicode/putil.h"
 
 /* Protos */
 static void ustr_resize(struct UString *s, int32_t len, UErrorCode *status);