diff --git a/pkgs/os-specific/darwin/apple-source-releases/ICU/package.nix b/pkgs/os-specific/darwin/apple-source-releases/ICU/package.nix
index 8f69b69a8082..937f5a5a14ca 100644
--- a/pkgs/os-specific/darwin/apple-source-releases/ICU/package.nix
+++ b/pkgs/os-specific/darwin/apple-source-releases/ICU/package.nix
@@ -21,7 +21,7 @@ let
   baseAttrs = finalAttrs: {
     releaseName = "ICU";
 
-    sourceRoot = "source/icuSources";
+    sourceRoot = "source/icu/icu4c/source";
 
     patches = [
       # Skip MessageFormatTest test, which is known to crash sometimes and should be suppressed if it does.
@@ -96,6 +96,12 @@ let
 
       substituteInPlace test/intltest/rbbitst.cpp \
         --replace-fail 'TESTCASE_AUTO(TestExternalBreakEngineWithFakeYue);' ""
+
+      # Otherwise `make install` is broken.
+      substituteInPlace Makefile.in \
+        --replace-fail '$(top_srcdir)/../LICENSE' "$NIX_BUILD_TOP/source/icu/LICENSE"
+      substituteInPlace config/dist-data.sh \
+        --replace-fail "\''${top_srcdir}/../LICENSE" "$NIX_BUILD_TOP/source/icu/LICENSE"
     '';
 
     # remove dependency on bootstrap-tools in early stdenv build
diff --git a/pkgs/os-specific/darwin/apple-source-releases/versions.json b/pkgs/os-specific/darwin/apple-source-releases/versions.json
index 86cb880470b9..43a899ff1b1a 100644
--- a/pkgs/os-specific/darwin/apple-source-releases/versions.json
+++ b/pkgs/os-specific/darwin/apple-source-releases/versions.json
@@ -8,8 +8,8 @@
     "version": "88"
   },
   "ICU": {
-    "hash": "sha256-p3CYITMljHVuwijeYnUbKaIWp/xPC4/hg1G1lO6PlFU=",
-    "version": "66108"
+    "hash": "sha256-CvpMLFNCEQ05t3nkzDyA9nsm3cmRgXG/QxbyiLpSpIs=",
+    "version": "74221"
   },
   "PowerManagement": {
     "hash": "sha256-bYGtYnBOcE5W03AZzfVTJXPZ6GgryGAMt/LgLPxFkVk=",