diff --git a/lib/internal/test_runner/runner.js b/lib/internal/test_runner/runner.js
index a5a53e44d29a..548ed006e152 100644
--- a/lib/internal/test_runner/runner.js
+++ b/lib/internal/test_runner/runner.js
@@ -182,7 +182,7 @@ function getRunArgs(path, { forceExit,
                             inspectPort,
                             testNamePatterns,
                             testSkipPatterns,
-                            testTagFilterExpressions,
+                            testTagFilters,
                             only,
                             hasFiles,
                             testFiles,
@@ -224,8 +224,8 @@ function getRunArgs(path, { forceExit,
   if (testSkipPatterns != null) {
     ArrayPrototypeForEach(testSkipPatterns, (pattern) => ArrayPrototypePush(runArgs, `--test-skip-pattern=${pattern}`));
   }
-  if (testTagFilterExpressions != null) {
-    ArrayPrototypeForEach(testTagFilterExpressions, (value) => ArrayPrototypePush(runArgs, `--experimental-test-tag-filter=${value}`));
+  if (testTagFilters != null) {
+    ArrayPrototypeForEach(testTagFilters, (value) => ArrayPrototypePush(runArgs, `--experimental-test-tag-filter=${value}`));
   }
   if (only === true) {
     ArrayPrototypePush(runArgs, '--test-only');
@@ -284,6 +284,14 @@ class FileTest extends Test {
     this.timeout = null;
   }
 
+  willBeFilteredByTags() {
+    // File wrappers have no tags of their own. Tag filtering applies to the
+    // tests inside the file, which run in a child process (or in-process
+    // import); filtering the wrapper would prevent the file from running at
+    // all.
+    return false;
+  }
+
   #skipReporting() {
     return this.#reportedChildren > 0 && (!this.error || this.error.failureType === kSubtestsFailed);
   }
@@ -864,7 +872,6 @@ function run(options = kEmptyObject) {
     });
   }
 
-  let testTagFilterExpressions = null;
   if (testTagFilters != null) {
     if (!ArrayIsArray(testTagFilters)) {
       testTagFilters = [testTagFilters];
@@ -876,10 +883,8 @@ function run(options = kEmptyObject) {
       testTagFilters = ArrayPrototypeMap(testTagFilters, (value, i) => (
         validateAndCanonicalizeTagFilter(value, `options.testTagFilters[${i}]`)
       ));
-      testTagFilterExpressions = testTagFilters;
     }
   }
-  testTagFilterExpressions ??= options.testTagFilterExpressions;
 
   validateOneOf(isolation, 'options.isolation', ['process', 'none']);
   validateBoolean(coverage, 'options.coverage');
@@ -982,7 +987,6 @@ function run(options = kEmptyObject) {
     testNamePatterns,
     testSkipPatterns,
     testTagFilters,
-    testTagFilterExpressions,
     hasFiles: files != null,
     globPatterns,
     only,
diff --git a/lib/internal/test_runner/test.js b/lib/internal/test_runner/test.js
index 38ce54e4ea9b..a728378182df 100644
--- a/lib/internal/test_runner/test.js
+++ b/lib/internal/test_runner/test.js
@@ -656,7 +656,7 @@ class Test extends AsyncResource {
       }
 
       if (isFilteringByTags) {
-        this.filteredByTag = !evaluateTagFilters(config.testTagFilters, this.tagSet);
+        this.filteredByTag = this.willBeFilteredByTags();
         if (!this.filteredByTag) {
           for (let t = this.parent; t !== null && t.filteredByTag; t = t.parent) {
             t.filteredByTag = false;
@@ -894,6 +894,10 @@ class Test extends AsyncResource {
     return false;
   }
 
+  willBeFilteredByTags() {
+    return !evaluateTagFilters(this.config.testTagFilters, this.tagSet);
+  }
+
   /**
    * Returns a name of the test prefixed by name of all its ancestors in ascending order, separated by a space
    * Ex."grandparent parent test"
diff --git a/lib/internal/test_runner/utils.js b/lib/internal/test_runner/utils.js
index 3590d3ef79b4..982fc6ef7bfe 100644
--- a/lib/internal/test_runner/utils.js
+++ b/lib/internal/test_runner/utils.js
@@ -273,7 +273,6 @@ function parseCommandLine() {
   let testNamePatterns = mapPatternFlagToRegExArray('--test-name-pattern');
   let testSkipPatterns = mapPatternFlagToRegExArray('--test-skip-pattern');
   let testTagFilters = null;
-  let testTagFilterExpressions = null;
 
   if (isChildProcessV8) {
     kBuiltinReporters.set('v8-serializer', 'internal/test_runner/reporter/v8-serializer');
@@ -309,19 +308,14 @@ function parseCommandLine() {
     const tagFilterFlag = getOptionValue('--experimental-test-tag-filter');
     if (tagFilterFlag?.length > 0) {
       emitExperimentalWarning('Test tags');
-      testTagFilterExpressions = tagFilterFlag;
-      // Validate at parent startup so a malformed flag fails fast,
-      // independent of isolation mode. Under isolation='process' the
-      // validated strings go unused at the parent (children re-validate
-      // and apply the filter); the validation here only surfaces input
-      // errors early.
-      const validated = ArrayPrototypeMap(
+      // File wrappers are exempt from tag filtering, so holding the filters
+      // in the parent is safe under any isolation mode; under
+      // isolation='process' the canonical values are re-emitted to the
+      // child processes, which apply the filter themselves.
+      testTagFilters = ArrayPrototypeMap(
         tagFilterFlag,
         (value, i) => validateAndCanonicalizeTagFilter(value, `--experimental-test-tag-filter[${i}]`),
       );
-      if (isolation === 'none') {
-        testTagFilters = validated;
-      }
     }
 
     if (isolation === 'none') {
@@ -365,7 +359,6 @@ function parseCommandLine() {
     const tagFilterFlag = getOptionValue('--experimental-test-tag-filter');
     if (tagFilterFlag?.length > 0) {
       emitExperimentalWarning('Test tags');
-      testTagFilterExpressions = tagFilterFlag;
       testTagFilters = ArrayPrototypeMap(
         tagFilterFlag,
         (value, i) => validateAndCanonicalizeTagFilter(value, `--experimental-test-tag-filter[${i}]`),
@@ -433,7 +426,6 @@ function parseCommandLine() {
     sourceMaps,
     testNamePatterns,
     testSkipPatterns,
-    testTagFilterExpressions,
     testTagFilters,
     timeout,
     updateSnapshots,
diff --git a/test/parallel/test-runner-tags-events.mjs b/test/parallel/test-runner-tags-events.mjs
index 2f275cf876f9..7d1b35f7349d 100644
--- a/test/parallel/test-runner-tags-events.mjs
+++ b/test/parallel/test-runner-tags-events.mjs
@@ -83,9 +83,6 @@ describe('tag-bearing event payloads', { concurrency: false }, () => {
   });
 
   it('test:pass fires only for selected tagged tests when filtered', async () => {
-    // isolation='none' so the parent applies the filter directly. Under
-    // 'process', the FileTest wrapper (which has no tags) would itself be
-    // filtered out by the include filter - same wart as --test-name-pattern.
     const stream = run({ files: [fixture], testTagFilters: ['db'], isolation: 'none' });
     stream.on('test:fail', common.mustNotCall());
     // 3 db-tagged tests pass + the db suite itself.
@@ -93,4 +90,15 @@ describe('tag-bearing event payloads', { concurrency: false }, () => {
     // eslint-disable-next-line no-unused-vars
     for await (const _ of stream);
   });
+
+  it('filtering under process isolation runs the file and filters inside it', async () => {
+    // The FileTest wrapper has no tags and must not be filtered out itself;
+    // the filter is re-emitted to the child process and applied there.
+    const stream = run({ files: [fixture], testTagFilters: ['db'], isolation: 'process' });
+    stream.on('test:fail', common.mustNotCall());
+    // 3 db-tagged tests pass + the db suite itself.
+    stream.on('test:pass', common.mustCall(4));
+    // eslint-disable-next-line no-unused-vars
+    for await (const _ of stream);
+  });
 });