diff --git a/.github/workflows/build-icu.yml b/.github/workflows/build-icu.yml
index c2463099499..a2e77a295b3 100644
--- a/.github/workflows/build-icu.yml
+++ b/.github/workflows/build-icu.yml
@@ -38,7 +38,7 @@ jobs:
           java-version: 11
           distribution: 'temurin'
       - name: Cache local Maven repository
-        uses: actions/cache@v3
+        uses: actions/cache@v4
         with:
           path: ~/.m2/repository
           key: ${{ runner.os }}-maven-${{ hashFiles('tools/**/pom.xml') }}
@@ -127,7 +127,7 @@ jobs:
           lfs: false # not needed here
           path: icu
       - name: Cache local Maven repository
-        uses: actions/cache@v3
+        uses: actions/cache@v4
         with:
           path: ~/.m2/repository
           key: ${{ runner.os }}-maven-${{ hashFiles('icu/tools/**/pom.xml') }}
diff --git a/.github/workflows/codeql-analysis.yml b/.github/workflows/codeql-analysis.yml
index 20fa8e87afa..33c2c07be1c 100644
--- a/.github/workflows/codeql-analysis.yml
+++ b/.github/workflows/codeql-analysis.yml
@@ -41,7 +41,7 @@ jobs:
         distribution: 'temurin'
     - name: Cache local Maven repository
       if: matrix.language == 'java'
-      uses: actions/cache@v3
+      uses: actions/cache@v4
       with:
         path: ~/.m2/repository
         key: ${{ runner.os }}-maven-${{ hashFiles('tools/**/pom.xml') }}
@@ -49,7 +49,7 @@ jobs:
           ${{ runner.os }}-maven-
     - name: Cache local npm repository
       if: matrix.language == 'javascript'
-      uses: actions/cache@v3
+      uses: actions/cache@v4
       with:
         path: ~/.npm
         key: ${{ runner.os }}-node-${{ hashFiles('**/package-lock.json') }}
diff --git a/.github/workflows/gh-pages.yml b/.github/workflows/gh-pages.yml
index 452c8512968..2e861d98e2e 100644
--- a/.github/workflows/gh-pages.yml
+++ b/.github/workflows/gh-pages.yml
@@ -20,7 +20,7 @@ jobs:
         with:
           lfs: false
       - name: Cache local npm repository
-        uses: actions/cache@v3
+        uses: actions/cache@v4
         with:
           path: ~/.npm
           key: ${{ runner.os }}-nodetr-${{ hashFiles('tools/scripts/tr-archive/package-lock.json') }}
diff --git a/.github/workflows/js.yml b/.github/workflows/js.yml
index ebf0ed9e93c..b3e1ead9337 100644
--- a/.github/workflows/js.yml
+++ b/.github/workflows/js.yml
@@ -21,7 +21,7 @@ jobs:
         lfs: false # not needed for this job, as we don’t currently do a Java build
     - uses: nodenv/actions/node-version@v3 # setup using .node-version
     - name: Cache webpack
-      uses: actions/cache@v3
+      uses: actions/cache@v4
       with:
         path: tools/cldr-apps/target/webpack_cache
         key: ${{ runner.os }}-webpack-${{ hashFiles('tools/cldr-apps/package*') }}-${{ hashFiles('tools/cldr-apps/src/**') }}
@@ -29,7 +29,7 @@ jobs:
           ${{ runner.os }}-webpack-
           webpack-
     - name: Cache npm repository
-      uses: actions/cache@v3
+      uses: actions/cache@v4
       with:
         path: ~/.npm
         key: ${{ runner.os }}-lint-${{ hashFiles('.github/workflows/js.yml') }}
diff --git a/.github/workflows/keyboard.yml b/.github/workflows/keyboard.yml
index 0c9b9fade12..95d972b158d 100644
--- a/.github/workflows/keyboard.yml
+++ b/.github/workflows/keyboard.yml
@@ -26,7 +26,7 @@ jobs:
           ref: ${{ github.event.inputs.git-ref }}
         if: github.event.inputs.git-ref != ''
       - name: Cache local npm repository
-        uses: actions/cache@v3
+        uses: actions/cache@v4
         with:
           path: ~/.npm
           key: ${{ runner.os }}-nodekbd-${{ hashFiles('**/package-lock.json') }}
diff --git a/.github/workflows/maven-release.yml b/.github/workflows/maven-release.yml
index 7bc61d7161e..2423d3518dd 100644
--- a/.github/workflows/maven-release.yml
+++ b/.github/workflows/maven-release.yml
@@ -9,7 +9,7 @@ jobs:
     steps:
       # since we have to checkout all branches, cache here
       - name: Cache .git
-        uses: actions/cache@v3
+        uses: actions/cache@v4
         with:
           path: .git
           key: git-${{ github.base_ref }}-${{ github.sha }}
@@ -27,7 +27,7 @@ jobs:
           java-version: 11
           distribution: 'temurin'
       - name: Cache local Maven repository
-        uses: actions/cache@v3
+        uses: actions/cache@v4
         with:
           path: ~/.m2/repository
           key: ${{ runner.os }}-maven-${{ hashFiles('tools/**/pom.xml') }}
diff --git a/.github/workflows/maven.yml b/.github/workflows/maven.yml
index e95987ec358..fb776d51443 100644
--- a/.github/workflows/maven.yml
+++ b/.github/workflows/maven.yml
@@ -16,7 +16,7 @@ jobs:
     steps:
       # since we have to checkout all branches, cache here
       - name: Cache .git
-        uses: actions/cache@v3
+        uses: actions/cache@v4
         with:
           path: .git
           key: git-${{ github.base_ref }}-${{ github.sha }}
@@ -32,7 +32,7 @@ jobs:
       - name: Lint GitHub Actions
         run: npx yaml-lint .github/workflows/*.yml
       - name: Cache local Maven repository
-        uses: actions/cache@v3
+        uses: actions/cache@v4
         with:
           path: ~/.m2/repository
           key: ${{ runner.os }}-mavenspotless-${{ hashFiles('tools/**/pom.xml') }}
@@ -62,14 +62,14 @@ jobs:
           java-version: 11
           distribution: 'temurin'
       - name: Cache local Maven repository
-        uses: actions/cache@v3
+        uses: actions/cache@v4
         with:
           path: ~/.m2/repository
           key: ${{ runner.os }}-maven-${{ hashFiles('tools/**/pom.xml') }}
           restore-keys: |
             ${{ runner.os }}-maven-
       - name: Cache local npm repository
-        uses: actions/cache@v3
+        uses: actions/cache@v4
         with:
           path: ~/.npm
           key: ${{ runner.os }}-node-${{ hashFiles('**/package-lock.json') }}
@@ -77,7 +77,7 @@ jobs:
             ${{ runner.os }}-node-
             node-
       - name: Cache webpack
-        uses: actions/cache@v3
+        uses: actions/cache@v4
         with:
           path: tools/cldr-apps/target/webpack_cache
           key: ${{ runner.os }}-webpack-${{ hashFiles('tools/cldr-apps/package*') }}-${{ hashFiles('tools/cldr-apps/src/**') }}
@@ -175,7 +175,7 @@ jobs:
           java-version: 11
           distribution: 'temurin'
       - name: Cache local Maven repository
-        uses: actions/cache@v3
+        uses: actions/cache@v4
         with:
           path: ~/.m2/repository
           key: ${{ runner.os }}-mavencheck-${{ hashFiles('tools/**/pom.xml') }}
diff --git a/.github/workflows/production.yml b/.github/workflows/production.yml
index f4c5fde4d74..f623e613aa8 100644
--- a/.github/workflows/production.yml
+++ b/.github/workflows/production.yml
@@ -32,14 +32,14 @@ jobs:
           java-version: 11
           distribution: 'temurin'
       - name: Cache local Maven repository
-        uses: actions/cache@v3
+        uses: actions/cache@v4
         with:
           path: ~/.m2/repository
           key: ${{ runner.os }}-maven-${{ hashFiles('tools/**/pom.xml') }}
           restore-keys: |
             ${{ runner.os }}-maven-
       - name: Cache local npm repository
-        uses: actions/cache@v3
+        uses: actions/cache@v4
         with:
           path: ~/.npm
           key: ${{ runner.os }}-node-${{ hashFiles('**/package-lock.json') }}
diff --git a/.github/workflows/staging.yml b/.github/workflows/staging.yml
index 9c86aea99a6..e0b3f546820 100644
--- a/.github/workflows/staging.yml
+++ b/.github/workflows/staging.yml
@@ -37,14 +37,14 @@ jobs:
           java-version: 11
           distribution: 'temurin'
       - name: Cache local Maven repository
-        uses: actions/cache@v3
+        uses: actions/cache@v4
         with:
           path: ~/.m2/repository
           key: ${{ runner.os }}-maven-${{ hashFiles('tools/**/pom.xml') }}
           restore-keys: |
             ${{ runner.os }}-maven-
       - name: Cache local npm repository
-        uses: actions/cache@v3
+        uses: actions/cache@v4
         with:
           path: ~/.npm
           key: ${{ runner.os }}-node-${{ hashFiles('**/package-lock.json') }}