diff --git a/.changeset/external-account-id.md b/.changeset/external-account-id.md
new file mode 100644
index 00000000000..3a772f68318
--- /dev/null
+++ b/.changeset/external-account-id.md
@@ -0,0 +1,5 @@
+---
+'@clerk/backend': patch
+---
+
+Add an optional `externalAccountId` to the backend `ExternalAccount` resource. For Google and Facebook accounts the resource `id` is the `idn_`-prefixed identification id, which `users.deleteUserExternalAccount()` rejects; `externalAccountId` now exposes the `eac_`-prefixed id those calls expect. For all other providers `id` is already the `eac_` id and `externalAccountId` is `undefined`, so use `externalAccountId ?? id` to get an id you can delete with.
diff --git a/packages/backend/src/api/resources/ExternalAccount.ts b/packages/backend/src/api/resources/ExternalAccount.ts
index a623a7f8a51..561efee0212 100644
--- a/packages/backend/src/api/resources/ExternalAccount.ts
+++ b/packages/backend/src/api/resources/ExternalAccount.ts
@@ -69,6 +69,14 @@ export class ExternalAccount {
      * An object holding information on the verification of this external account.
      */
     readonly verification: Verification | null,
+    /**
+     * The `eac_`-prefixed id of the external account resource, which is the id
+     * `users.deleteUserExternalAccount()` expects. Only returned for Google and
+     * Facebook accounts, where `id` holds the `idn_` identification id instead;
+     * for other providers it is `undefined` and `id` is already the `eac_` value.
+     * Use `externalAccountId ?? id` to get an id you can delete with.
+     */
+    readonly externalAccountId?: string,
   ) {}
 
   static fromJSON(data: ExternalAccountJSON): ExternalAccount {
@@ -88,6 +96,7 @@ export class ExternalAccount {
       data.public_metadata,
       data.label,
       data.verification && Verification.fromJSON(data.verification),
+      data.external_account_id,
     );
   }
 }
diff --git a/packages/backend/src/api/resources/JSON.ts b/packages/backend/src/api/resources/JSON.ts
index 3193401523d..65fc8b3a9ac 100644
--- a/packages/backend/src/api/resources/JSON.ts
+++ b/packages/backend/src/api/resources/JSON.ts
@@ -231,6 +231,10 @@ export interface EnterpriseAccountJSON extends ClerkResourceJSON {
 
 export interface ExternalAccountJSON extends ClerkResourceJSON {
   object: typeof ObjectType.ExternalAccount;
+  /**
+   * The `eac_`-prefixed external account id. Only present for Google and Facebook accounts.
+   */
+  external_account_id?: string;
   provider: string;
   identification_id: string;
   provider_user_id: string;
diff --git a/packages/backend/src/api/resources/__tests__/ExternalAccount.test.ts b/packages/backend/src/api/resources/__tests__/ExternalAccount.test.ts
new file mode 100644
index 00000000000..2faa1047033
--- /dev/null
+++ b/packages/backend/src/api/resources/__tests__/ExternalAccount.test.ts
@@ -0,0 +1,56 @@
+import { describe, expect, it } from 'vitest';
+
+import { ExternalAccount } from '../ExternalAccount';
+import type { ExternalAccountJSON } from '../JSON';
+
+describe('ExternalAccount', () => {
+  describe('fromJSON', () => {
+    const base = {
+      object: 'external_account',
+      provider: 'oauth_google',
+      provider_user_id: '1029384756',
+      approved_scopes: 'email profile',
+      email_address: 'jane@example.com',
+      first_name: 'Jane',
+      last_name: 'Doe',
+      image_url: 'https://img.clerk.com/jane.png',
+      username: 'jane',
+      phone_number: null,
+      public_metadata: {},
+      label: null,
+      verification: null,
+    };
+
+    it('maps external_account_id to externalAccountId for Google/Facebook accounts', () => {
+      // Google/Facebook responses set `id` to the `idn_` identification id and add `external_account_id`.
+      const data = {
+        ...base,
+        id: 'idn_2ABXLLckIF5kLikvzAVRxuuN31M',
+        external_account_id: 'eac_2ABXLObDmeHsnLsLgOd5panvOPJ',
+        identification_id: 'idn_2ABXLLckIF5kLikvzAVRxuuN31M',
+      } as ExternalAccountJSON;
+
+      const externalAccount = ExternalAccount.fromJSON(data);
+
+      expect(externalAccount.externalAccountId).toBe('eac_2ABXLObDmeHsnLsLgOd5panvOPJ');
+      // `id` and `identificationId` keep the `idn_` value for these providers.
+      expect(externalAccount.id).toBe('idn_2ABXLLckIF5kLikvzAVRxuuN31M');
+      expect(externalAccount.identificationId).toBe('idn_2ABXLLckIF5kLikvzAVRxuuN31M');
+    });
+
+    it('leaves externalAccountId undefined for other providers, where id is already the eac_ id', () => {
+      // Other providers omit `external_account_id`; `id` already holds the `eac_` value.
+      const data = {
+        ...base,
+        provider: 'oauth_github',
+        id: 'eac_2ABXLObDmeHsnLsLgOd5panvOPJ',
+        identification_id: 'idn_2ABXLLckIF5kLikvzAVRxuuN31M',
+      } as ExternalAccountJSON;
+
+      const externalAccount = ExternalAccount.fromJSON(data);
+
+      expect(externalAccount.externalAccountId).toBeUndefined();
+      expect(externalAccount.id).toBe('eac_2ABXLObDmeHsnLsLgOd5panvOPJ');
+    });
+  });
+});