diff --git a/icu4c/source/i18n/olsontz.cpp b/icu4c/source/i18n/olsontz.cpp
index b69e76e640e..184549f7f6a 100644
--- a/icu4c/source/i18n/olsontz.cpp
+++ b/icu4c/source/i18n/olsontz.cpp
@@ -616,8 +616,10 @@ OlsonTimeZone::initTransitionRules(UErrorCode& status) {
     UnicodeString tzid;
     getID(tzid);
 
-    UnicodeString stdName = tzid + "(STD)";
-    UnicodeString dstName = tzid + "(DST)";
+    UnicodeString _std("(STD)", -1, US_INV);
+    UnicodeString _dst("(DST)", -1, US_INV);
+    UnicodeString stdName = tzid + _std;
+    UnicodeString dstName = tzid + _dst;
 
     int32_t raw, dst;
     if (transitionCount > 0) {
diff --git a/icu4c/source/i18n/simpletz.cpp b/icu4c/source/i18n/simpletz.cpp
index ef4cdd06b2b..ff7cd8f3d87 100644
--- a/icu4c/source/i18n/simpletz.cpp
+++ b/icu4c/source/i18n/simpletz.cpp
@@ -1021,6 +1021,8 @@ SimpleTimeZone::initTransitionRules(UErrorCode& status) {
         DateTimeRule* dtRule;
         DateTimeRule::TimeRuleType timeRuleType;
         UDate firstStdStart, firstDstStart;
+        UnicodeString dst("(DST)", -1, US_INV);  // These work even if
+        UnicodeString std("(STD)", -1, US_INV);  // UCONFIG_NO_CONVERSION is set.
 
         // Create a TimeZoneRule for daylight saving time
         timeRuleType = (startTimeMode == STANDARD_TIME) ? DateTimeRule::STANDARD_TIME :
@@ -1043,7 +1045,7 @@ SimpleTimeZone::initTransitionRules(UErrorCode& status) {
             return;
         }
         // For now, use ID + "(DST)" as the name
-        dstRule = new AnnualTimeZoneRule(tzid+"(DST)", getRawOffset(), getDSTSavings(),
+        dstRule = new AnnualTimeZoneRule(tzid+dst, getRawOffset(), getDSTSavings(),
             dtRule, startYear, AnnualTimeZoneRule::MAX_YEAR);
  
         // Calculate the first DST start time
@@ -1067,7 +1069,7 @@ SimpleTimeZone::initTransitionRules(UErrorCode& status) {
             break;
         }
         // For now, use ID + "(STD)" as the name
-        stdRule = new AnnualTimeZoneRule(tzid+"(STD)", getRawOffset(), 0,
+        stdRule = new AnnualTimeZoneRule(tzid+std, getRawOffset(), 0,
             dtRule, startYear, AnnualTimeZoneRule::MAX_YEAR);
 
         // Calculate the first STD start time
@@ -1075,10 +1077,10 @@ SimpleTimeZone::initTransitionRules(UErrorCode& status) {
 
         // Create a TimeZoneRule for initial time
         if (firstStdStart < firstDstStart) {
-            initialRule = new InitialTimeZoneRule(tzid+"(DST)", getRawOffset(), dstRule->getDSTSavings());
+            initialRule = new InitialTimeZoneRule(tzid+dst, getRawOffset(), dstRule->getDSTSavings());
             firstTransition = new TimeZoneTransition(firstStdStart, *initialRule, *stdRule);
         } else {
-            initialRule = new InitialTimeZoneRule(tzid+"(STD)", getRawOffset(), 0);
+            initialRule = new InitialTimeZoneRule(tzid+std, getRawOffset(), 0);
             firstTransition = new TimeZoneTransition(firstDstStart, *initialRule, *dstRule);
         }
         
diff --git a/icu4c/source/i18n/smpdtfmt.cpp b/icu4c/source/i18n/smpdtfmt.cpp
index 67ca7b40877..b21b08edbca 100644
--- a/icu4c/source/i18n/smpdtfmt.cpp
+++ b/icu4c/source/i18n/smpdtfmt.cpp
@@ -950,7 +950,7 @@ SimpleDateFormat::zoneIDCanonicalize(UnicodeString &zid) const
             int32_t len;
             const UChar* alias = ures_getNextString(zoneAliases,&len,NULL,&status);
             if ( zid.compare(alias)==0 ) {
-                zid.setTo(UnicodeString(currentZoneString,(const char *)0));
+                zid.setTo(UnicodeString(currentZoneString, -1, US_INV));
                 zid.findAndReplace(colon,solidus);
                 ures_close(zoneAliases);
                 ures_close(currentZone);