diff --git a/Package.swift b/Package.swift
index 06d305f..6d464dc 100644
--- a/Package.swift
+++ b/Package.swift
@@ -3,6 +3,18 @@
 
 import PackageDescription
 
+let allPlatforms: [Platform] = [
+    .iOS,
+    .macOS,
+    .tvOS,
+    .watchOS,
+    .macCatalyst,
+    .driverKit,
+    .android,
+    .linux,
+    .windows,
+  ]
+
 var buildSettings: [CXXSetting] = [
   .define("DEBUG", to: "1", .when(configuration: .debug)),
   .define("U_ATTRIBUTE_DEPRECATED", to: ""),
@@ -10,18 +22,7 @@ var buildSettings: [CXXSetting] = [
   .define("U_SHOW_INTERNAL_API", to: "1"),
   .define("U_STATIC_IMPLEMENTATION"),
   .define("U_TIMEZONE", to: "_timezone", .when(platforms: [.windows])),
-  .define(
-    "U_TIMEZONE", to: "timezone",
-    .when(platforms: [
-      .iOS,
-      .macOS,
-      .tvOS,
-      .watchOS,
-      .macCatalyst,
-      .driverKit,
-      .android,
-      .linux,
-    ])),
+  .define("U_TIMEZONE", to: "timezone", .when(platforms: allPlatforms.filter({ $0 != .windows }))),
   .define("U_TIMEZONE_PACKAGE", to: "\"icutz44l\""),
   .define("U_HAVE_TZSET", to: "0", .when(platforms: [.wasi])),
   .define("U_HAVE_TZNAME", to: "0", .when(platforms: [.wasi])),
@@ -45,7 +46,8 @@ var buildSettings: [CXXSetting] = [
 
   // Where data are stored
   .define("ICU_DATA_DIR", to: "\"/usr/share/icu/\""),
-  .define("USE_PACKAGE_DATA", to: "1"),
+  .define("ICU_DATA_DIR_PREFIX_ENV_VAR", to: "\"ICU_DATA_DIR_PREFIX\""),
+  .define("USE_PACKAGE_DATA", to: "1", .when(platforms: allPlatforms.filter({ $0 != .android }))),
   .define("APPLE_ICU_CHANGES", to: "1"),
 
   .headerSearchPath("common"),
diff --git a/icuSources/common/udata.cpp b/icuSources/common/udata.cpp
index 3357e18..aa508a3 100644
--- a/icuSources/common/udata.cpp
+++ b/icuSources/common/udata.cpp
@@ -701,7 +701,7 @@ openCommonData(const char *path,          /*  Path from OpenChoice?          */
             if(gCommonICUDataArray[commonDataIndex] != nullptr) {
                 return gCommonICUDataArray[commonDataIndex];
             }
-#if !defined(ICU_DATA_DIR_WINDOWS)
+#if defined(USE_PACKAGE_DATA) && !defined(ICU_DATA_DIR_WINDOWS)
 // When using the Windows system data, we expect only a single data file.
             int32_t i;
             for(i = 0; i < commonDataIndex; ++i) {
@@ -726,7 +726,7 @@ openCommonData(const char *path,          /*  Path from OpenChoice?          */
             setCommonICUDataPointer(uprv_getICUData_conversion(), false, pErrorCode);
         }
         */
-#if !defined(ICU_DATA_DIR_WINDOWS)
+#if defined(USE_PACKAGE_DATA) && !defined(ICU_DATA_DIR_WINDOWS)
 // When using the Windows system data, we expect only a single data file.
         setCommonICUDataPointer(&U_ICUDATA_ENTRY_POINT, false, pErrorCode);
         {