diff --git a/icu4c/source/data/misc/zoneinfo64.txt b/icu4c/source/data/misc/zoneinfo64.txt
index c0d27420d53..821cafad4bf 100644
--- a/icu4c/source/data/misc/zoneinfo64.txt
+++ b/icu4c/source/data/misc/zoneinfo64.txt
@@ -3,9 +3,9 @@
 // License & terms of use: http://www.unicode.org/copyright.html
 //---------------------------------------------------------
 // Build tool:  tz2icu
-// Build date:  Thu Oct 21 02:21:19 2021
+// Build date:  Sun Oct 24 18:18:10 2021
 // tz database: ftp://ftp.iana.org/tz/
-// tz version:  2021a2
+// tz version:  2021a3
 // ICU version: 70.1
 //---------------------------------------------------------
 // >> !!! >>   THIS IS A MACHINE-GENERATED FILE   << !!! <<
@@ -13,7 +13,7 @@
 //---------------------------------------------------------
 
 zoneinfo64:table(nofallback) {
- TZVersion { "2021a2" }
+ TZVersion { "2021a3" }
  Zones:array { 
   /* ACT */ :int { 356 } //Z#0
   /* AET */ :int { 368 } //Z#1
@@ -1362,22 +1362,22 @@ zoneinfo64:table(nofallback) {
   } //Z#268
   /* Asia/Gaza */ :table {
     transPre32:intvector { -1, 2109557424 }
-    trans:intvector { -933638400, -923097600, -919036800, -857347200, -844300800, -825811200, -812678400, -794188800, -779846400, -762652800, -748310400, -731116800, -399088800, -386650800, -368330400, -355114800, -336790800, -323654400, -305168400, -292032000, -273632400, -260496000, -242096400, -228960000, -210560400, -197424000, -178938000, -165801600, -147402000, -134265600, -115866000, -102643200, -84330000, -81313200, 142380000, 150843600, 167176800, 178664400, 334101600, 337730400, 452642400, 462319200, 482277600, 494370000, 516751200, 526424400, 545436000, 558478800, 576626400, 589323600, 609890400, 620773200, 638316000, 651618000, 669765600, 683672400, 701820000, 715726800, 733701600, 747176400, 765151200, 778021200, 796600800, 810075600, 828655200, 843170400, 860104800, 874620000, 891554400, 906069600, 924213600, 939934800, 956268000, 971989200, 987717600, 1003438800, 1019167200, 1034888400, 1050616800, 1066338000, 1082066400, 1096581600, 1113516000, 1128380400, 1143842400, 1158872400, 1175378400, 1189638000, 1206655200, 1219957200, 1238104800, 1252015200, 1269640860, 1281474000, 1301608860, 1312146000, 1333058400, 1348178400, 1364508000, 1380229200, 1395957600, 1414098000, 1427493600, 1445551200, 1458946800, 1477692000, 1490396400, 1509141600, 1521846000, 1540591200, 1553810400, 1572037200, 1585346400, 1603490400 }
+    trans:intvector { -933638400, -923097600, -919036800, -857347200, -844300800, -825811200, -812678400, -794188800, -779846400, -762652800, -748310400, -731116800, -399088800, -386650800, -368330400, -355114800, -336790800, -323654400, -305168400, -292032000, -273632400, -260496000, -242096400, -228960000, -210560400, -197424000, -178938000, -165801600, -147402000, -134265600, -115866000, -102643200, -84330000, -81313200, 142380000, 150843600, 167176800, 178664400, 334101600, 337730400, 452642400, 462319200, 482277600, 494370000, 516751200, 526424400, 545436000, 558478800, 576626400, 589323600, 609890400, 620773200, 638316000, 651618000, 669765600, 683672400, 701820000, 715726800, 733701600, 747176400, 765151200, 778021200, 796600800, 810075600, 828655200, 843170400, 860104800, 874620000, 891554400, 906069600, 924213600, 939934800, 956268000, 971989200, 987717600, 1003438800, 1019167200, 1034888400, 1050616800, 1066338000, 1082066400, 1096581600, 1113516000, 1128380400, 1143842400, 1158872400, 1175378400, 1189638000, 1206655200, 1219957200, 1238104800, 1252015200, 1269640860, 1281474000, 1301608860, 1312146000, 1333058400, 1348178400, 1364508000, 1380229200, 1395957600, 1414098000, 1427493600, 1445551200, 1458946800, 1477692000, 1490396400, 1509141600, 1521846000, 1540591200, 1553810400, 1572037200, 1585346400, 1603490400, 1616796000, 1635458400 }
     typeOffsets:intvector { 8272, 0, 7200, 0, 7200, 3600 }
-    typeMap:bin { "01020102010201020102010201020102010201020102010201020102010201020102010201020102010201020102010201020102010201020102010201020102010201020102010201020102010201020102010201020102010201020102010201020102010201020102010201020102010201" }
+    typeMap:bin { "010201020102010201020102010201020102010201020102010201020102010201020102010201020102010201020102010201020102010201020102010201020102010201020102010201020102010201020102010201020102010201020102010201020102010201020102010201020102010201" }
     finalRule { "Palestine" }
     finalRaw:int { 7200 }
-    finalYear:int { 2021 }
+    finalYear:int { 2022 }
   } //Z#269
   /* Asia/Harbin */ :int { 315 } //Z#270
   /* Asia/Hebron */ :table {
     transPre32:intvector { -1, 2109557273 }
-    trans:intvector { -933638400, -923097600, -919036800, -857347200, -844300800, -825811200, -812678400, -794188800, -779846400, -762652800, -748310400, -731116800, -399088800, -386650800, -368330400, -355114800, -336790800, -323654400, -305168400, -292032000, -273632400, -260496000, -242096400, -228960000, -210560400, -197424000, -178938000, -165801600, -147402000, -134265600, -115866000, -102643200, -84330000, -81313200, 142380000, 150843600, 167176800, 178664400, 334101600, 337730400, 452642400, 462319200, 482277600, 494370000, 516751200, 526424400, 545436000, 558478800, 576626400, 589323600, 609890400, 620773200, 638316000, 651618000, 669765600, 683672400, 701820000, 715726800, 733701600, 747176400, 765151200, 778021200, 796600800, 810075600, 828655200, 843170400, 860104800, 874620000, 891554400, 906069600, 924213600, 939934800, 956268000, 971989200, 987717600, 1003438800, 1019167200, 1034888400, 1050616800, 1066338000, 1082066400, 1096581600, 1113516000, 1128380400, 1143842400, 1158872400, 1175378400, 1189638000, 1206655200, 1220216400, 1238104800, 1252015200, 1269554400, 1281474000, 1301608860, 1312146000, 1314655200, 1317330000, 1333058400, 1348178400, 1364508000, 1380229200, 1395957600, 1414098000, 1427493600, 1445551200, 1458946800, 1477692000, 1490396400, 1509141600, 1521846000, 1540591200, 1553810400, 1572037200, 1585346400, 1603490400 }
+    trans:intvector { -933638400, -923097600, -919036800, -857347200, -844300800, -825811200, -812678400, -794188800, -779846400, -762652800, -748310400, -731116800, -399088800, -386650800, -368330400, -355114800, -336790800, -323654400, -305168400, -292032000, -273632400, -260496000, -242096400, -228960000, -210560400, -197424000, -178938000, -165801600, -147402000, -134265600, -115866000, -102643200, -84330000, -81313200, 142380000, 150843600, 167176800, 178664400, 334101600, 337730400, 452642400, 462319200, 482277600, 494370000, 516751200, 526424400, 545436000, 558478800, 576626400, 589323600, 609890400, 620773200, 638316000, 651618000, 669765600, 683672400, 701820000, 715726800, 733701600, 747176400, 765151200, 778021200, 796600800, 810075600, 828655200, 843170400, 860104800, 874620000, 891554400, 906069600, 924213600, 939934800, 956268000, 971989200, 987717600, 1003438800, 1019167200, 1034888400, 1050616800, 1066338000, 1082066400, 1096581600, 1113516000, 1128380400, 1143842400, 1158872400, 1175378400, 1189638000, 1206655200, 1220216400, 1238104800, 1252015200, 1269554400, 1281474000, 1301608860, 1312146000, 1314655200, 1317330000, 1333058400, 1348178400, 1364508000, 1380229200, 1395957600, 1414098000, 1427493600, 1445551200, 1458946800, 1477692000, 1490396400, 1509141600, 1521846000, 1540591200, 1553810400, 1572037200, 1585346400, 1603490400, 1616796000, 1635458400 }
     typeOffsets:intvector { 8423, 0, 7200, 0, 7200, 3600 }
-    typeMap:bin { "010201020102010201020102010201020102010201020102010201020102010201020102010201020102010201020102010201020102010201020102010201020102010201020102010201020102010201020102010201020102010201020102010201020102010201020102010201020102010201" }
+    typeMap:bin { "0102010201020102010201020102010201020102010201020102010201020102010201020102010201020102010201020102010201020102010201020102010201020102010201020102010201020102010201020102010201020102010201020102010201020102010201020102010201020102010201" }
     finalRule { "Palestine" }
     finalRaw:int { 7200 }
-    finalYear:int { 2021 }
+    finalYear:int { 2022 }
   } //Z#271
   /* Asia/Ho_Chi_Minh */ :table {
     trans:intvector { -2004073600, -1851577590, -852105600, -782643600, -767869200, -718095600, -457776000, -315648000, 171820800 }
@@ -3114,7 +3114,7 @@ zoneinfo64:table(nofallback) {
     8, -30, -1, 7200, 1, 3, 1, -1, 7200, 1, 3600
   } //_#19
   Palestine:intvector {
-    2, 24, -7, 0, 0, 9, 24, -7, 3600, 0, 3600
+    2, 24, -7, 0, 0, 9, -31, -6, 3600, 0, 3600
   } //_#20
   Para:intvector {
     9, 1, -1, 0, 0, 2, 22, -1, 0, 0, 3600
diff --git a/icu4j/main/shared/data/icutzdata.jar b/icu4j/main/shared/data/icutzdata.jar
index 635b62ca5a2..ba74c78e948 100644
--- a/icu4j/main/shared/data/icutzdata.jar
+++ b/icu4j/main/shared/data/icutzdata.jar
@@ -1,3 +1,3 @@
 version https://git-lfs.github.com/spec/v1
-oid sha256:c0df0c63a3a9e3150b5c528fd82097c2d5fdc70564367198bdd5d21740b83646
-size 96399
+oid sha256:9191c37c0e9f2aab1d5b6d5d6a7d48f480a00daf3abe3a8aff97e0de999fc650
+size 96394