diff --git a/.github/workflows/cifuzz.yml b/.github/workflows/cifuzz.yml
index 458fd060f03..37ac83bf5b5 100644
--- a/.github/workflows/cifuzz.yml
+++ b/.github/workflows/cifuzz.yml
@@ -8,6 +8,7 @@ on:
       - '**.cpp'
       - '**.cxx'
       - '**.h'
+      - 'testdata/**'
       - '.github/workflows/**'
   push:
     branches:
@@ -19,6 +20,7 @@ on:
       - '**.cpp'
       - '**.cxx'
       - '**.h'
+      - 'testdata/**'
       - '.github/workflows/**'
   workflow_dispatch:
 permissions: {}
diff --git a/.github/workflows/icu4c.yml b/.github/workflows/icu4c.yml
index d4e42be6e99..06c9bc25a7b 100644
--- a/.github/workflows/icu4c.yml
+++ b/.github/workflows/icu4c.yml
@@ -12,11 +12,13 @@ on:
       - 'maint/maint*'
     paths:
       - 'icu4c/**'
+      - 'testdata/**'
       - '.github/workflows/**'
   pull_request:
     branches: '**'
     paths:
       - 'icu4c/**'
+      - 'testdata/**'
       - '.github/workflows/**'
   workflow_dispatch:
     # To trigger the Env Test workflow manually, follow the instructions in
diff --git a/.github/workflows/icu4j.yml b/.github/workflows/icu4j.yml
index 28baf7920fa..868f3dd8bc9 100644
--- a/.github/workflows/icu4j.yml
+++ b/.github/workflows/icu4j.yml
@@ -12,11 +12,13 @@ on:
       - 'maint/maint*'
     paths:
       - 'icu4j/**'
+      - 'testdata/**'
       - '.github/workflows/**'
   pull_request:
     branches: '**'
     paths:
       - 'icu4j/**'
+      - 'testdata/**'
       - '.github/workflows/**'
   workflow_dispatch:
     # To trigger the Env Test workflow manually, follow the instructions in
diff --git a/.github/workflows/icu_exhaustive_tests.yml b/.github/workflows/icu_exhaustive_tests.yml
index fe992f74b01..88f25ed9c8d 100644
--- a/.github/workflows/icu_exhaustive_tests.yml
+++ b/.github/workflows/icu_exhaustive_tests.yml
@@ -19,6 +19,7 @@ on:
     paths:
       - 'icu4c/**'
       - 'icu4j/**'
+      - 'testdata/**'
       - '.github/workflows/**'
   schedule:
     # Runs daily on default branch (main) only.
diff --git a/.github/workflows/icu_valgrind.yml b/.github/workflows/icu_valgrind.yml
index 7128e1fc617..1f406e8fe23 100644
--- a/.github/workflows/icu_valgrind.yml
+++ b/.github/workflows/icu_valgrind.yml
@@ -13,11 +13,13 @@ on:
       - 'maint/maint*'
     paths:
       - 'icu4c/**'
+      - 'testdata/**'
       - '.github/workflows/**'
   pull_request:
     branches: '**'
     paths:
       - 'icu4c/**'
+      - 'testdata/**'
       - '.github/workflows/**'
 
 # For non-release branches (namely: PRs), only run CI on the most recent commit. Cancel