diff --git a/goldens/aria/accordion/testing/index.api.md b/goldens/aria/accordion/testing/index.api.md
new file mode 100644
index 000000000000..ef4d0432fa9a
--- /dev/null
+++ b/goldens/aria/accordion/testing/index.api.md
@@ -0,0 +1,59 @@
+## API Report File for "@angular/aria_accordion_testing"
+
+> Do not edit this file. It is a report generated by [API Extractor](https://api-extractor.com/).
+
+```ts
+
+import * as _angular_cdk_testing from '@angular/cdk/testing';
+import { BaseHarnessFilters } from '@angular/cdk/testing';
+import { ComponentHarness } from '@angular/cdk/testing';
+import { ContentContainerComponentHarness } from '@angular/cdk/testing';
+import { HarnessPredicate } from '@angular/cdk/testing';
+
+// @public
+export class AccordionGroupHarness extends ComponentHarness {
+    getAccordions(filters?: AccordionHarnessFilters): Promise<AccordionHarness[]>;
+    // (undocumented)
+    static hostSelector: string;
+    static with(options?: AccordionGroupHarnessFilters): HarnessPredicate<AccordionGroupHarness>;
+}
+
+// @public
+export interface AccordionGroupHarnessFilters extends BaseHarnessFilters {
+}
+
+// @public
+export class AccordionHarness extends ContentContainerComponentHarness<AccordionSection> {
+    blur(): Promise<void>;
+    collapse(): Promise<void>;
+    expand(): Promise<void>;
+    focus(): Promise<void>;
+    protected getRootHarnessLoader(): Promise<_angular_cdk_testing.HarnessLoader>;
+    getTitle(): Promise<string>;
+    // (undocumented)
+    static hostSelector: string;
+    isDisabled(): Promise<boolean>;
+    isExpanded(): Promise<boolean>;
+    isFocused(): Promise<boolean>;
+    toggle(): Promise<void>;
+    static with(options?: AccordionHarnessFilters): HarnessPredicate<AccordionHarness>;
+}
+
+// @public
+export interface AccordionHarnessFilters extends BaseHarnessFilters {
+    disabled?: boolean;
+    expanded?: boolean;
+    title?: string | RegExp;
+}
+
+// @public
+export enum AccordionSection {
+    // (undocumented)
+    PANEL = "[ngAccordionPanel]",
+    // (undocumented)
+    TRIGGER = "[ngAccordionTrigger]"
+}
+
+// (No @packageDocumentation comment for this package)
+
+```
diff --git a/src/aria/accordion/BUILD.bazel b/src/aria/accordion/BUILD.bazel
index 51ffb8340196..59483aa59b55 100644
--- a/src/aria/accordion/BUILD.bazel
+++ b/src/aria/accordion/BUILD.bazel
@@ -13,6 +13,7 @@ ng_project(
         "//src/aria/private",
         "//src/cdk/a11y",
         "//src/cdk/bidi",
+        "//src/cdk/testing",
     ],
 )
 
@@ -26,7 +27,9 @@ ng_project(
         ":accordion",
         "//:node_modules/@angular/core",
         "//:node_modules/@angular/platform-browser",
+        "//src/cdk/testing",
         "//src/cdk/testing/private",
+        "//src/cdk/testing/testbed",
     ],
 )
 
diff --git a/src/aria/accordion/testing/BUILD.bazel b/src/aria/accordion/testing/BUILD.bazel
new file mode 100644
index 000000000000..daefc5897c1a
--- /dev/null
+++ b/src/aria/accordion/testing/BUILD.bazel
@@ -0,0 +1,42 @@
+load("//tools:defaults.bzl", "ng_project", "ng_web_test_suite", "ts_project")
+
+package(default_visibility = ["//visibility:public"])
+
+ts_project(
+    name = "testing",
+    srcs = glob(
+        ["**/*.ts"],
+        exclude = ["**/*.spec.ts"],
+    ),
+    deps = [
+        "//:node_modules/@angular/core",
+        "//src/cdk/testing",
+    ],
+)
+
+filegroup(
+    name = "source-files",
+    srcs = glob(["**/*.ts"]),
+)
+
+ng_project(
+    name = "unit_tests_lib",
+    testonly = True,
+    srcs = glob(["**/*.spec.ts"]),
+    deps = [
+        ":testing",
+        "//:node_modules/@angular/core",
+        "//:node_modules/@angular/platform-browser",
+        "//src/aria/accordion",
+        "//src/cdk/testing",
+        "//src/cdk/testing/private",
+        "//src/cdk/testing/testbed",
+    ],
+)
+
+ng_web_test_suite(
+    name = "unit_tests",
+    deps = [
+        ":unit_tests_lib",
+    ],
+)
diff --git a/src/aria/accordion/testing/accordion-harness-filters.ts b/src/aria/accordion/testing/accordion-harness-filters.ts
new file mode 100644
index 000000000000..7c736ddb1c51
--- /dev/null
+++ b/src/aria/accordion/testing/accordion-harness-filters.ts
@@ -0,0 +1,22 @@
+/**
+ * @license
+ * Copyright Google LLC All Rights Reserved.
+ *
+ * Use of this source code is governed by an MIT-style license that can be
+ * found in the LICENSE file at https://angular.dev/license
+ */
+
+import {BaseHarnessFilters} from '@angular/cdk/testing';
+
+/** Filters for locating an `AccordionHarness`. */
+export interface AccordionHarnessFilters extends BaseHarnessFilters {
+  /** Only find instances whose title text matches the given value. */
+  title?: string | RegExp;
+  /** Only find instances whose expanded state matches the given value. */
+  expanded?: boolean;
+  /** Only find instances whose disabled state matches the given value. */
+  disabled?: boolean;
+}
+
+/** Filters for locating an `AccordionGroupHarness`. */
+export interface AccordionGroupHarnessFilters extends BaseHarnessFilters {}
diff --git a/src/aria/accordion/testing/accordion-harness.spec.ts b/src/aria/accordion/testing/accordion-harness.spec.ts
new file mode 100644
index 000000000000..cd43d4096b21
--- /dev/null
+++ b/src/aria/accordion/testing/accordion-harness.spec.ts
@@ -0,0 +1,150 @@
+/**
+ * @license
+ * Copyright Google LLC All Rights Reserved.
+ *
+ * Use of this source code is governed by an MIT-style license that can be
+ * found in the LICENSE file at https://angular.dev/license
+ */
+
+import {Component} from '@angular/core';
+import {TestBed} from '@angular/core/testing';
+import {TestbedHarnessEnvironment} from '@angular/cdk/testing/testbed';
+import {ComponentHarness} from '@angular/cdk/testing';
+import {AccordionHarness, AccordionGroupHarness} from './accordion-harness';
+import {AccordionGroup, AccordionPanel, AccordionTrigger} from '../index';
+
+/** Lightweight test harness to test querying inside the accordion body panel. */
+class TestButtonHarness extends ComponentHarness {
+  static hostSelector = 'button.test-button';
+
+  async getText(): Promise<string> {
+    return (await this.host()).text();
+  }
+}
+
+describe('Accordion Harnesses', () => {
+  let fixture: any;
+  let loader: any;
+
+  @Component({
+    imports: [AccordionGroup, AccordionPanel, AccordionTrigger],
+    template: `
+      <div ngAccordionGroup>
+        <div #panel1="ngAccordionPanel" ngAccordionPanel>
+          <button class="test-button">Inside Content 1</button>
+        </div>
+        <button ngAccordionTrigger [panel]="panel1">Section 1</button>
+
+        <div #panel2="ngAccordionPanel" ngAccordionPanel>Content 2</div>
+        <button ngAccordionTrigger [panel]="panel2" disabled>Section 2</button>
+      </div>
+    `,
+  })
+  class AccordionHarnessTestComponent {}
+
+  beforeEach(() => {
+    TestBed.configureTestingModule({
+      imports: [AccordionHarnessTestComponent],
+    });
+    fixture = TestBed.createComponent(AccordionHarnessTestComponent);
+    fixture.detectChanges();
+    loader = TestbedHarnessEnvironment.loader(fixture);
+  });
+
+  it('should find accordion group and list all scoped accordions using getAccordions', async () => {
+    const group = await loader.getHarness(AccordionGroupHarness);
+    const accordions = await group.getAccordions();
+
+    expect(accordions.length).toBe(2);
+    expect(await accordions[0].getTitle()).toBe('Section 1');
+    expect(await accordions[1].getTitle()).toBe('Section 2');
+  });
+
+  it('should find all individual accordions via standard root loader', async () => {
+    const accordions = await loader.getAllHarnesses(AccordionHarness);
+    expect(accordions.length).toBe(2);
+  });
+
+  it('should filter accordions by title', async () => {
+    const accordions = await loader.getAllHarnesses(AccordionHarness.with({title: 'Section 1'}));
+    expect(accordions.length).toBe(1);
+    expect(await accordions[0].getTitle()).toBe('Section 1');
+  });
+
+  it('should filter accordions by expanded state', async () => {
+    const accordion = await loader.getHarness(AccordionHarness.with({title: 'Section 1'}));
+    await accordion.expand();
+
+    const expandedAccordions = await loader.getAllHarnesses(
+      AccordionHarness.with({expanded: true}),
+    );
+    expect(expandedAccordions.length).toBe(1);
+    expect(await expandedAccordions[0].getTitle()).toBe('Section 1');
+  });
+
+  it('should filter accordions by disabled state', async () => {
+    const disabledAccordions = await loader.getAllHarnesses(
+      AccordionHarness.with({disabled: true}),
+    );
+    expect(disabledAccordions.length).toBe(1);
+    expect(await disabledAccordions[0].getTitle()).toBe('Section 2');
+  });
+
+  it('should get the title of the accordion', async () => {
+    const accordion = await loader.getHarness(AccordionHarness.with({title: 'Section 1'}));
+    expect(await accordion.getTitle()).toBe('Section 1');
+  });
+
+  it('should correctly report the expanded state of an accordion', async () => {
+    const accordion = await loader.getHarness(AccordionHarness.with({title: 'Section 1'}));
+    expect(await accordion.isExpanded()).toBeFalse();
+  });
+
+  it('should correctly report the disabled state of an accordion', async () => {
+    const activeAccordion = await loader.getHarness(AccordionHarness.with({title: 'Section 1'}));
+    const disabledAccordion = await loader.getHarness(AccordionHarness.with({title: 'Section 2'}));
+
+    expect(await activeAccordion.isDisabled()).toBeFalse();
+    expect(await disabledAccordion.isDisabled()).toBeTrue();
+  });
+
+  it('expands a collapsed accordion using the expand method', async () => {
+    const accordion = await loader.getHarness(AccordionHarness.with({title: 'Section 1'}));
+
+    await accordion.expand();
+
+    expect(await accordion.isExpanded()).toBeTrue();
+  });
+
+  it('collapses an expanded accordion using the collapse method', async () => {
+    const accordion = await loader.getHarness(AccordionHarness.with({title: 'Section 1'}));
+    await accordion.expand();
+
+    await accordion.collapse();
+
+    expect(await accordion.isExpanded()).toBeFalse();
+  });
+
+  it('toggles the expanded state of an accordion using the toggle method', async () => {
+    const accordion = await loader.getHarness(AccordionHarness.with({title: 'Section 1'}));
+
+    await accordion.toggle();
+
+    expect(await accordion.isExpanded()).toBeTrue();
+  });
+
+  it('should support focusing and blurring accordion triggers', async () => {
+    const accordion = await loader.getHarness(AccordionHarness.with({title: 'Section 1'}));
+    await accordion.focus();
+    expect(await accordion.isFocused()).toBeTrue();
+
+    await accordion.blur();
+    expect(await accordion.isFocused()).toBeFalse();
+  });
+
+  it('should query components inside the accordion panel using ContentContainerComponentHarness', async () => {
+    const accordion = await loader.getHarness(AccordionHarness.with({title: 'Section 1'}));
+    const button = await accordion.getHarness(TestButtonHarness);
+    expect(await button.getText()).toBe('Inside Content 1');
+  });
+});
diff --git a/src/aria/accordion/testing/accordion-harness.ts b/src/aria/accordion/testing/accordion-harness.ts
new file mode 100644
index 000000000000..d37c40bdac01
--- /dev/null
+++ b/src/aria/accordion/testing/accordion-harness.ts
@@ -0,0 +1,119 @@
+/**
+ * @license
+ * Copyright Google LLC All Rights Reserved.
+ *
+ * Use of this source code is governed by an MIT-style license that can be
+ * found in the LICENSE file at https://angular.dev/license
+ */
+
+import {
+  ComponentHarness,
+  ContentContainerComponentHarness,
+  HarnessPredicate,
+} from '@angular/cdk/testing';
+import {AccordionHarnessFilters, AccordionGroupHarnessFilters} from './accordion-harness-filters';
+
+/** Selectors for the sections that may contain user content. */
+export enum AccordionSection {
+  TRIGGER = '[ngAccordionTrigger]',
+  PANEL = '[ngAccordionPanel]',
+}
+
+/** Harness for interacting with a standard ngAccordion item in tests. */
+export class AccordionHarness extends ContentContainerComponentHarness<AccordionSection> {
+  static hostSelector = '[ngAccordionTrigger]';
+
+  /**
+   * Gets a `HarnessPredicate` that can be used to search for an accordion
+   * with specific attributes.
+   */
+  static with(options: AccordionHarnessFilters = {}): HarnessPredicate<AccordionHarness> {
+    return new HarnessPredicate(AccordionHarness, options)
+      .addOption('title', options.title, (harness, title) =>
+        HarnessPredicate.stringMatches(harness.getTitle(), title),
+      )
+      .addOption(
+        'expanded',
+        options.expanded,
+        async (harness, expanded) => (await harness.isExpanded()) === expanded,
+      )
+      .addOption(
+        'disabled',
+        options.disabled,
+        async (harness, disabled) => (await harness.isDisabled()) === disabled,
+      );
+  }
+
+  /** Overrides the internal loader to automatically resolve queries inside the associated panel. */
+  protected override async getRootHarnessLoader() {
+    const panelId = await (await this.host()).getAttribute('aria-controls');
+    const documentRoot = await this.documentRootLocatorFactory().rootHarnessLoader();
+    return documentRoot.getChildLoader(`[ngAccordionPanel][id="${panelId}"]`);
+  }
+
+  /** Whether the accordion is expanded. */
+  async isExpanded(): Promise<boolean> {
+    return (await (await this.host()).getAttribute('aria-expanded')) === 'true';
+  }
+
+  /** Whether the accordion is disabled. */
+  async isDisabled(): Promise<boolean> {
+    return (await (await this.host()).getAttribute('aria-disabled')) === 'true';
+  }
+
+  /** Gets the title text of the accordion. */
+  async getTitle(): Promise<string> {
+    return (await this.host()).text();
+  }
+
+  /** Toggles the expanded state of the accordion by clicking on the trigger. */
+  async toggle(): Promise<void> {
+    await (await this.host()).click();
+  }
+
+  /** Expands the accordion if collapsed. */
+  async expand(): Promise<void> {
+    if (!(await this.isExpanded())) {
+      await this.toggle();
+    }
+  }
+
+  /** Collapses the accordion if expanded. */
+  async collapse(): Promise<void> {
+    if (await this.isExpanded()) {
+      await this.toggle();
+    }
+  }
+
+  /** Focuses the accordion trigger. */
+  async focus(): Promise<void> {
+    await (await this.host()).focus();
+  }
+
+  /** Blurs the accordion trigger. */
+  async blur(): Promise<void> {
+    await (await this.host()).blur();
+  }
+
+  /** Whether the accordion trigger is focused. */
+  async isFocused(): Promise<boolean> {
+    return (await this.host()).isFocused();
+  }
+}
+
+/** Harness for interacting with an `ngAccordionGroup` in tests. */
+export class AccordionGroupHarness extends ComponentHarness {
+  static hostSelector = '[ngAccordionGroup]';
+
+  /**
+   * Gets a `HarnessPredicate` that can be used to search for an accordion group with specific attributes.
+   */
+  static with(options: AccordionGroupHarnessFilters = {}): HarnessPredicate<AccordionGroupHarness> {
+    return new HarnessPredicate(AccordionGroupHarness, options);
+  }
+
+  /** Gets all accordions within this group. */
+  async getAccordions(filters: AccordionHarnessFilters = {}): Promise<AccordionHarness[]> {
+    return this.locatorForAll(AccordionHarness.with(filters))();
+  }
+}
diff --git a/src/aria/accordion/testing/index.ts b/src/aria/accordion/testing/index.ts
new file mode 100644
index 000000000000..52b3c7a5156f
--- /dev/null
+++ b/src/aria/accordion/testing/index.ts
@@ -0,0 +1,9 @@
+/**
+ * @license
+ * Copyright Google LLC All Rights Reserved.
+ *
+ * Use of this source code is governed by an MIT-style license that can be
+ * found in the LICENSE file at https://angular.dev/license
+ */
+
+export * from './public-api';
diff --git a/src/aria/accordion/testing/public-api.ts b/src/aria/accordion/testing/public-api.ts
new file mode 100644
index 000000000000..acb15bdb15bd
--- /dev/null
+++ b/src/aria/accordion/testing/public-api.ts
@@ -0,0 +1,10 @@
+/**
+ * @license
+ * Copyright Google LLC All Rights Reserved.
+ *
+ * Use of this source code is governed by an MIT-style license that can be
+ * found in the LICENSE file at https://angular.dev/license
+ */
+
+export * from './accordion-harness';
+export * from './accordion-harness-filters';
diff --git a/src/aria/config.bzl b/src/aria/config.bzl
index 291412b5a3fb..de62934edcf6 100644
--- a/src/aria/config.bzl
+++ b/src/aria/config.bzl
@@ -1,6 +1,7 @@
 # List of all entry-points of the Angular Aria package.
 ARIA_ENTRYPOINTS = [
     "accordion",
+    "accordion/testing",
     "combobox",
     "grid",
     "listbox",