diff --git a/entrypoints.json b/entrypoints.json
index caa92a7604..96c3f52e73 100644
--- a/entrypoints.json
+++ b/entrypoints.json
@@ -16,6 +16,10 @@
     "typings": "./lib/auth/index.d.ts",
     "dist": "./lib/auth/index.js"
   },
+  "firebase-admin/fpnv": {
+    "typings": "./lib/fpnv/index.d.ts",
+    "dist": "./lib/fpnv/index.js"
+  },
   "firebase-admin/database": {
     "typings": "./lib/database/index.d.ts",
     "dist": "./lib/database/index.js"
diff --git a/etc/firebase-admin.fpnv.api.md b/etc/firebase-admin.fpnv.api.md
new file mode 100644
index 0000000000..8a390a79fb
--- /dev/null
+++ b/etc/firebase-admin.fpnv.api.md
@@ -0,0 +1,37 @@
+## API Report File for "firebase-admin.fpnv"
+
+> Do not edit this file. It is a report generated by [API Extractor](https://api-extractor.com/).
+
+```ts
+
+import { Agent } from 'http';
+
+// @public
+export class Fpnv {
+    // Warning: (ae-forgotten-export) The symbol "App" needs to be exported by the entry point index.d.ts
+    get app(): App;
+    // Warning: (ae-forgotten-export) The symbol "FirebasePhoneNumberTokenVerifier" needs to be exported by the entry point index.d.ts
+    //
+    // (undocumented)
+    protected readonly fpnvVerifier: FirebasePhoneNumberTokenVerifier;
+    // (undocumented)
+    verifyToken(fpnvJwt: string): Promise<FpnvToken>;
+}
+
+// @public
+export interface FpnvToken {
+    [key: string]: any;
+    aud: string[];
+    exp: number;
+    getPhoneNumber(): string;
+    iat: number;
+    iss: string;
+    jti: string;
+    nonce: string;
+    sub: string;
+}
+
+// @public
+export function getFirebasePnv(app?: App): Fpnv;
+
+```
diff --git a/package.json b/package.json
index a17a1e291f..7a33f881be 100644
--- a/package.json
+++ b/package.json
@@ -73,6 +73,9 @@
       "auth": [
         "lib/auth"
       ],
+      "fpnv": [
+        "lib/fpnv"
+      ],
       "eventarc": [
         "lib/eventarc"
       ],
@@ -134,6 +137,11 @@
       "require": "./lib/auth/index.js",
       "import": "./lib/esm/auth/index.js"
     },
+    "./fpnv": {
+      "types": "./lib/fpnv/index.d.ts",
+      "require": "./lib/fpnv/index.js",
+      "import": "./lib/esm/fpnv/index.js"
+    },
     "./database": {
       "types": "./lib/database/index.d.ts",
       "require": "./lib/database/index.js",
diff --git a/src/fpnv/fpnv-api-client-internal.ts b/src/fpnv/fpnv-api-client-internal.ts
new file mode 100644
index 0000000000..22a3a85ff3
--- /dev/null
+++ b/src/fpnv/fpnv-api-client-internal.ts
@@ -0,0 +1,71 @@
+/*!
+ * @license
+ * Copyright 2025 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+import { PrefixedFirebaseError } from '../utils/error';
+
+export interface FirebasePhoneNumberTokenInfo {
+  /** Documentation URL. */
+  url: string;
+  /** verify API name. */
+  verifyApiName: string;
+  /** The JWT full name. */
+  jwtName: string;
+  /** The JWT short name. */
+  shortName: string;
+  /** The JWT typ" (Type) */
+  typ: string;
+}
+
+export const CLIENT_CERT_URL = 'https://www.googleapis.com/robot/v1/metadata/x509/securetoken@system.gserviceaccount.com';
+
+export const PN_TOKEN_INFO: FirebasePhoneNumberTokenInfo = {
+  url: 'https://firebase.google.com/docs/phone-number-verification',
+  verifyApiName: 'verifyToken()',
+  jwtName: 'Firebase Phone Verification token',
+  shortName: 'FPNV token',
+  typ: 'JWT',
+};
+
+export const FPNV_ERROR_CODE_MAPPING = {
+  INVALID_ARGUMENT: 'invalid-argument',
+  INVALID_TOKEN: 'invalid-token',
+  EXPIRED_TOKEN: 'expired-token',
+} satisfies Record<string, FpnvErrorCode>;
+
+export type FpnvErrorCode =
+  | 'invalid-argument'
+  | 'invalid-token'
+  | 'expired-token'
+
+/**
+ * Firebase Phone Number Verification error code structure. This extends `PrefixedFirebaseError`.
+ *
+ * @param code - The error code.
+ * @param message - The error message.
+ * @constructor
+ */
+export class FirebaseFpnvError extends PrefixedFirebaseError {
+  constructor(code: FpnvErrorCode, message: string) {
+    super('fpnv', code, message);
+
+    /* tslint:disable:max-line-length */
+    // Set the prototype explicitly. See the following link for more details:
+    // https://github.com/Microsoft/TypeScript/wiki/Breaking-Changes#extending-built-ins-like-error-array-and-map-may-no-longer-work
+    /* tslint:enable:max-line-length */
+    (this as any).__proto__ = FirebaseFpnvError.prototype;
+  }
+}
\ No newline at end of file
diff --git a/src/fpnv/fpnv-api.ts b/src/fpnv/fpnv-api.ts
new file mode 100644
index 0000000000..1c298302a6
--- /dev/null
+++ b/src/fpnv/fpnv-api.ts
@@ -0,0 +1,80 @@
+/*!
+ * @license
+ * Copyright 2025 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+
+/**
+ * Interface representing a Fpnv token.
+ */
+export interface FpnvToken {
+    /**
+     * The issuer identifier for the issuer of the response.
+     * This value is a URL with the format
+     * `https://firebaseappcheck.googleapis.com/<PROJECT_NUMBER>`, where `<PROJECT_NUMBER>` is the
+     * same project number specified in the {@link FpnvToken.aud} property.
+     */
+    iss: string;
+
+    /**
+     * The audience for which this token is intended.
+     * This value is a JSON array of two strings, the first is the project number of your
+     * Firebase project, and the second is the project ID of the same project.
+     */
+    aud: string[];
+
+    /**
+     * The Fpnv token's expiration time, in seconds since the Unix epoch. That is, the
+     * time at which this Fpnv token expires and should no longer be considered valid.
+     */
+    exp: number;
+
+    /**
+     * The Fpnv token's issued-at time, in seconds since the Unix epoch. That is, the
+     * time at which this Fpnv token was issued and should start to be considered
+     * valid.
+     */
+    iat: number;
+
+    /**
+     * The phone number of User.
+     */
+    sub: string;
+
+    /**
+     * Unique ID.
+     */
+    jti: string;
+
+    /**
+     * Unique ID.
+     */
+    nonce: string;
+
+    /**
+     * The corresponding user's phone number.
+     * This value is not actually one of the JWT token claims. It is added as a
+     * convenience, and is set as the value of the {@link FpnvToken.sub} property.
+     */
+    getPhoneNumber(): string;
+
+    /**
+     * Other arbitrary claims included in the token.
+     */
+    [key: string]: any;
+}
+
+export { FpnvErrorCode, FirebaseFpnvError } from './fpnv-api-client-internal';
+
diff --git a/src/fpnv/fpnv.ts b/src/fpnv/fpnv.ts
new file mode 100644
index 0000000000..5d72b480f5
--- /dev/null
+++ b/src/fpnv/fpnv.ts
@@ -0,0 +1,58 @@
+/*!
+ * @license
+ * Copyright 2025 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+import { App } from '../app';
+import { FpnvToken } from './fpnv-api';
+import { FirebasePhoneNumberTokenVerifier } from './token-verifier';
+import { CLIENT_CERT_URL, PN_TOKEN_INFO } from './fpnv-api-client-internal';
+
+/**
+ * Fpnv service bound to the provided app.
+ */
+export class Fpnv {
+  private readonly appInternal: App;
+  protected readonly fpnvVerifier: FirebasePhoneNumberTokenVerifier;
+
+  /**
+   * @param app - The app for this `Fpnv` service.
+   * @constructor
+   * @internal
+   */
+  constructor(app: App) {
+
+    this.appInternal = app;
+    this.fpnvVerifier = new FirebasePhoneNumberTokenVerifier(
+      CLIENT_CERT_URL,
+      'https://fpnv.googleapis.com/projects/',
+      PN_TOKEN_INFO,
+      app
+    );
+  }
+
+  /**
+   * Returns the app associated with this `Fpnv` instance.
+   *
+   * @returns The app associated with this `Fpnv` instance.
+   */
+  get app(): App {
+    return this.appInternal;
+  }
+
+  public async verifyToken(fpnvJwt: string): Promise<FpnvToken> {
+    return await this.fpnvVerifier.verifyJWT(fpnvJwt);
+  }
+}
diff --git a/src/fpnv/index.ts b/src/fpnv/index.ts
new file mode 100644
index 0000000000..90d96bff92
--- /dev/null
+++ b/src/fpnv/index.ts
@@ -0,0 +1,64 @@
+/**
+ * Firebase Phone Number Verification.
+ *
+ * @packageDocumentation
+ */
+
+/*!
+ * @license
+ * Copyright 2025 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+import { App, getApp } from '../app';
+import { FirebaseApp } from '../app/firebase-app';
+import { Fpnv } from './fpnv';
+
+export {
+  Fpnv
+} from './fpnv';
+
+export {
+  FpnvToken,
+} from './fpnv-api'
+
+/**
+ * Gets the {@link Fpnv} service for the default app or a
+ * given app.
+ *
+ * `getFirebasePnv()` can be called with no arguments to access the default app's
+ * {@link Fpnv} service or as `getFirebasePnv(app)` to access the
+ * {@link Fpnv} service associated with a specific app.
+ *
+ * @example
+ * ```javascript
+ * // Get the Fpnv service for the default app
+ * const defaultFpnv = getFirebasePnv();
+ * ```
+ *
+ * @example
+ * ```javascript
+ * // Get the Fpnv service for a given app
+ * const otherFpnv = getFirebasePnv(otherApp);
+ * ```
+ *
+ */
+export function getFirebasePnv(app?: App): Fpnv {
+  if (typeof app === 'undefined') {
+    app = getApp();
+  }
+
+  const firebaseApp: FirebaseApp = app as FirebaseApp;
+  return firebaseApp.getOrInitService('fpnv', (app) => new Fpnv(app));
+}
diff --git a/src/fpnv/token-verifier.ts b/src/fpnv/token-verifier.ts
new file mode 100644
index 0000000000..3debad2595
--- /dev/null
+++ b/src/fpnv/token-verifier.ts
@@ -0,0 +1,205 @@
+/*!
+ * @license
+ * Copyright 2025 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+import { App } from '../app';
+import { FirebaseFpnvError, FpnvToken } from './fpnv-api';
+import * as util from '../utils/index';
+import * as validator from '../utils/validator';
+import {
+  DecodedToken, decodeJwt, JwtError, JwtErrorCode,
+  PublicKeySignatureVerifier, ALGORITHM_ES256, SignatureVerifier,
+} from '../utils/jwt';
+import { FirebasePhoneNumberTokenInfo, FPNV_ERROR_CODE_MAPPING } from './fpnv-api-client-internal';
+
+export class FirebasePhoneNumberTokenVerifier {
+
+  private readonly shortNameArticle: string;
+  private readonly signatureVerifier: SignatureVerifier;
+
+  constructor(
+    clientCertUrl: string,
+        private issuer: string,
+        private tokenInfo: FirebasePhoneNumberTokenInfo,
+        private readonly app: App
+  ) {
+
+    if (!validator.isURL(clientCertUrl)) {
+      throw new FirebaseFpnvError(
+        FPNV_ERROR_CODE_MAPPING.INVALID_ARGUMENT,
+        'The provided public client certificate URL is an invalid URL.',
+      );
+    } else if (!validator.isURL(issuer)) {
+      throw new FirebaseFpnvError(
+        FPNV_ERROR_CODE_MAPPING.INVALID_ARGUMENT,
+        'The provided JWT issuer is an invalid URL.',
+      );
+    } else if (!validator.isNonNullObject(tokenInfo)) {
+      throw new FirebaseFpnvError(
+        FPNV_ERROR_CODE_MAPPING.INVALID_ARGUMENT,
+        'The provided JWT information is not an object or null.',
+      );
+    } else if (!validator.isURL(tokenInfo.url)) {
+      throw new FirebaseFpnvError(
+        FPNV_ERROR_CODE_MAPPING.INVALID_ARGUMENT,
+        'The provided JWT verification documentation URL is invalid.',
+      );
+    } else if (!validator.isNonEmptyString(tokenInfo.verifyApiName)) {
+      throw new FirebaseFpnvError(
+        FPNV_ERROR_CODE_MAPPING.INVALID_ARGUMENT,
+        'The JWT verify API name must be a non-empty string.',
+      );
+    } else if (!validator.isNonEmptyString(tokenInfo.jwtName)) {
+      throw new FirebaseFpnvError(
+        FPNV_ERROR_CODE_MAPPING.INVALID_ARGUMENT,
+        'The JWT public full name must be a non-empty string.',
+      );
+    } else if (!validator.isNonEmptyString(tokenInfo.shortName)) {
+      throw new FirebaseFpnvError(
+        FPNV_ERROR_CODE_MAPPING.INVALID_ARGUMENT,
+        'The JWT public short name must be a non-empty string.',
+      );
+    }
+    this.shortNameArticle = tokenInfo.shortName.charAt(0).match(/[aeiou]/i) ? 'an' : 'a';
+
+    this.signatureVerifier =
+            PublicKeySignatureVerifier.withCertificateUrl(clientCertUrl, app.options.httpAgent);
+
+    // For backward compatibility, the project ID is validated in the verification call.
+  }
+
+  public async verifyJWT(jwtToken: string): Promise<FpnvToken> {
+    if (!validator.isString(jwtToken)) {
+      throw new FirebaseFpnvError(
+        FPNV_ERROR_CODE_MAPPING.INVALID_TOKEN,
+        `First argument to ${this.tokenInfo.verifyApiName} must be a string.`,
+      );
+    }
+
+    const projectId = await this.ensureProjectId();
+    const decoded = await this.decodeAndVerify(jwtToken, projectId);
+    const decodedIdToken = decoded.payload as FpnvToken;
+    decodedIdToken.getPhoneNumber = () => decodedIdToken.sub;
+    return decodedIdToken;
+  }
+
+  private async ensureProjectId(): Promise<string> {
+    const projectId = await util.findProjectId(this.app);
+    if (!validator.isNonEmptyString(projectId)) {
+      throw new FirebaseFpnvError(
+        FPNV_ERROR_CODE_MAPPING.INVALID_ARGUMENT,
+        'Must initialize app with a cert credential or set your Firebase project ID as the ' +
+                `GOOGLE_CLOUD_PROJECT environment variable to call ${this.tokenInfo.verifyApiName}.`);
+    }
+    return projectId;
+  }
+
+  private async decodeAndVerify(
+    token: string,
+    projectId: string,
+  ): Promise<DecodedToken> {
+    const decodedToken = await this.safeDecode(token);
+    this.verifyContent(decodedToken, projectId);
+    await this.verifySignature(token);
+    return decodedToken;
+  }
+
+  private async safeDecode(jwtToken: string): Promise<DecodedToken> {
+    try {
+      return await decodeJwt(jwtToken);
+    } catch (err) {
+      if (err.code === JwtErrorCode.INVALID_ARGUMENT) {
+        const verifyJwtTokenDocsMessage = ` See ${this.tokenInfo.url} ` +
+                    `for details on how to retrieve ${this.shortNameArticle} ${this.tokenInfo.shortName}.`;
+        const errorMessage = `Decoding ${this.tokenInfo.jwtName} failed. Make sure you passed ` +
+                    `the entire string JWT which represents ${this.shortNameArticle} ` +
+                    `${this.tokenInfo.shortName}.` + verifyJwtTokenDocsMessage;
+        throw new FirebaseFpnvError(FPNV_ERROR_CODE_MAPPING.INVALID_ARGUMENT,
+          errorMessage);
+      }
+      throw new FirebaseFpnvError(FPNV_ERROR_CODE_MAPPING.INVALID_ARGUMENT, err.message);
+    }
+  }
+
+  private verifyContent(
+    fullDecodedToken: DecodedToken,
+    projectId: string | null,
+  ): void {
+    const header = fullDecodedToken && fullDecodedToken.header;
+    const payload = fullDecodedToken && fullDecodedToken.payload;
+
+    const scopedProjectId = `${this.issuer}${projectId}`;
+    const projectIdMatchMessage = ` Make sure the ${this.tokenInfo.shortName} comes from the same ` +
+            'Firebase project as the service account used to authenticate this SDK.';
+    const verifyJwtTokenDocsMessage = ` See ${this.tokenInfo.url} ` +
+            `for details on how to retrieve ${this.shortNameArticle} ${this.tokenInfo.shortName}.`;
+
+    let errorMessage: string | undefined;
+
+    // JWT Header
+    if (typeof header.kid === 'undefined') {
+      errorMessage = `${this.tokenInfo.jwtName} has no "kid" claim.`;
+      errorMessage += verifyJwtTokenDocsMessage;
+    } else if (header.alg !== ALGORITHM_ES256) {
+      errorMessage = `${this.tokenInfo.jwtName} has incorrect algorithm. Expected ` + 
+      `"${ALGORITHM_ES256}" but got "${header.alg}". ${verifyJwtTokenDocsMessage}`;
+    } else if (header.typ !== this.tokenInfo.typ) {
+      errorMessage = `${this.tokenInfo.jwtName} has incorrect typ. Expected "${this.tokenInfo.typ}" but got ` +
+                 `"${header.typ}". ${verifyJwtTokenDocsMessage}`;
+    }
+    // FPNV Token
+    else if (!validator.isNonEmptyArray(payload.aud) || !payload.aud.includes(scopedProjectId)) {
+      errorMessage = `${this.tokenInfo.jwtName} has incorrect "aud" (audience) claim. Expected ` +
+        `"${scopedProjectId}" to be one of "${payload.aud}". ${projectIdMatchMessage} ${verifyJwtTokenDocsMessage}`;
+    } else if (typeof payload.sub !== 'string') {
+      errorMessage = `${this.tokenInfo.jwtName} has no "sub" (subject) claim. ${verifyJwtTokenDocsMessage}`;
+    } else if (payload.sub === '') {
+      errorMessage = `${this.tokenInfo.jwtName} has an empty "sub" (subject) claim. ${verifyJwtTokenDocsMessage}`;
+    }
+
+    if (errorMessage) {
+      throw new FirebaseFpnvError(FPNV_ERROR_CODE_MAPPING.INVALID_ARGUMENT, errorMessage);
+    }
+  }
+
+  private async verifySignature(jwtToken: string): Promise<void> {
+    try {
+      return await this.signatureVerifier.verify(jwtToken);
+    } catch (error) {
+      throw this.mapJwtErrorToAuthError(error);
+    }
+  }
+
+  private mapJwtErrorToAuthError(error: JwtError): Error {
+    const verifyJwtTokenDocsMessage = ` See ${this.tokenInfo.url} ` +
+            `for details on how to retrieve ${this.shortNameArticle} ${this.tokenInfo.shortName}.`;
+    if (error.code === JwtErrorCode.TOKEN_EXPIRED) {
+      const errorMessage = `${this.tokenInfo.jwtName} has expired. Get a fresh ${this.tokenInfo.shortName}` +
+                ` from your client app and try again. ${verifyJwtTokenDocsMessage}`;
+      return new FirebaseFpnvError(FPNV_ERROR_CODE_MAPPING.EXPIRED_TOKEN, errorMessage);
+    } else if (error.code === JwtErrorCode.INVALID_SIGNATURE) {
+      const errorMessage = `${this.tokenInfo.jwtName} has invalid signature. ${verifyJwtTokenDocsMessage}`;
+      return new FirebaseFpnvError(FPNV_ERROR_CODE_MAPPING.INVALID_ARGUMENT, errorMessage);
+    } else if (error.code === JwtErrorCode.NO_MATCHING_KID) {
+      const errorMessage = `${this.tokenInfo.jwtName} has "kid" claim which does not ` +
+                `correspond to a known public key. Most likely the ${this.tokenInfo.shortName} ` +
+                'is expired, so get a fresh token from your client app and try again.';
+      return new FirebaseFpnvError(FPNV_ERROR_CODE_MAPPING.INVALID_ARGUMENT, errorMessage);
+    }
+    return new FirebaseFpnvError(FPNV_ERROR_CODE_MAPPING.INVALID_ARGUMENT, error.message);
+  }
+
+}
diff --git a/src/utils/jwt.ts b/src/utils/jwt.ts
index 9a66494482..f3e4ba0744 100644
--- a/src/utils/jwt.ts
+++ b/src/utils/jwt.ts
@@ -21,6 +21,7 @@ import { HttpClient, HttpRequestConfig, RequestResponseError } from '../utils/ap
 import { Agent } from 'http';
 
 export const ALGORITHM_RS256: jwt.Algorithm = 'RS256' as const;
+export const ALGORITHM_ES256: jwt.Algorithm = 'ES256' as const;
 
 // `jsonwebtoken` converts errors from the `getKey` callback to its own `JsonWebTokenError` type
 // and prefixes the error message with the following. Use the prefix to identify errors thrown