diff --git a/packages/nodes-base/credentials/SalesforceJwtApi.credentials.ts b/packages/nodes-base/credentials/SalesforceJwtApi.credentials.ts
index a2262c45d48..d97ef162752 100644
--- a/packages/nodes-base/credentials/SalesforceJwtApi.credentials.ts
+++ b/packages/nodes-base/credentials/SalesforceJwtApi.credentials.ts
@@ -2,6 +2,7 @@ import type { AxiosRequestConfig } from 'axios';
 import axios from 'axios';
 import jwt from 'jsonwebtoken';
 import moment from 'moment-timezone';
+
 import { formatPrivateKey } from '@utils/utilities';
 import type {
 	ICredentialDataDecryptedObject,
@@ -63,6 +64,15 @@ export class SalesforceJwtApi implements ICredentialType {
 			description:
 				'Use the multiline editor. Make sure it is in standard PEM key format:<br />-----BEGIN PRIVATE KEY-----<br />KEY DATA GOES HERE<br />-----END PRIVATE KEY-----',
 		},
+		{
+			displayName: 'My Domain URL',
+			name: 'myDomainUrl',
+			type: 'string',
+			default: '',
+			placeholder: 'https://mycompany.my.salesforce.com',
+			description:
+				"Your org's My Domain URL (e.g. <code>https://mycompany.my.salesforce.com</code>). Required for Spring '26 and later orgs; leave blank to keep the default audience used by earlier orgs.",
+		},
 	];
 
 	async authenticate(
@@ -70,10 +80,7 @@ export class SalesforceJwtApi implements ICredentialType {
 		requestOptions: IHttpRequestOptions,
 	): Promise<IHttpRequestOptions> {
 		const now = moment().unix();
-		const authUrl =
-			credentials.environment === 'sandbox'
-				? 'https://test.salesforce.com'
-				: 'https://login.salesforce.com';
+		const authUrl = resolveAuthUrl(credentials);
 		const privateKey = formatPrivateKey(credentials.privateKey as string);
 		const signature = jwt.sign(
 			{
@@ -118,9 +125,19 @@ export class SalesforceJwtApi implements ICredentialType {
 	test: ICredentialTestRequest = {
 		request: {
 			baseURL:
-				'={{$credentials?.environment === "sandbox" ? "https://test.salesforce.com" : "https://login.salesforce.com"}}',
+				'={{$credentials?.myDomainUrl ? $credentials.myDomainUrl.replace(/\\/$/, "") : ($credentials?.environment === "sandbox" ? "https://test.salesforce.com" : "https://login.salesforce.com")}}',
 			url: '/services/oauth2/userinfo',
 			method: 'GET',
 		},
 	};
 }
+
+export function resolveAuthUrl(credentials: ICredentialDataDecryptedObject): string {
+	const myDomainUrl = ((credentials.myDomainUrl as string | undefined) ?? '').replace(/\/$/, '');
+	if (myDomainUrl) {
+		return myDomainUrl;
+	}
+	return credentials.environment === 'sandbox'
+		? 'https://test.salesforce.com'
+		: 'https://login.salesforce.com';
+}
diff --git a/packages/nodes-base/credentials/test/SalesforceJwtApi.credentials.test.ts b/packages/nodes-base/credentials/test/SalesforceJwtApi.credentials.test.ts
new file mode 100644
index 00000000000..f1201c69067
--- /dev/null
+++ b/packages/nodes-base/credentials/test/SalesforceJwtApi.credentials.test.ts
@@ -0,0 +1,211 @@
+import axios from 'axios';
+import jwt from 'jsonwebtoken';
+import type { IHttpRequestOptions } from 'n8n-workflow';
+
+import { SalesforceJwtApi, resolveAuthUrl } from '../SalesforceJwtApi.credentials';
+
+jest.mock('axios');
+jest.mock('jsonwebtoken', () => ({
+	sign: jest.fn(),
+}));
+jest.mock('@utils/utilities', () => ({
+	formatPrivateKey: (key: string) => key,
+}));
+
+describe('SalesforceJwtApi Credential', () => {
+	const credential = new SalesforceJwtApi();
+	const mockedAxios = axios as unknown as jest.Mock;
+	const mockedSign = jwt.sign as unknown as jest.Mock;
+
+	const baseCredentials = {
+		clientId: 'connected-app-client-id',
+		username: 'user@example.com',
+		privateKey: '-----BEGIN PRIVATE KEY-----\nkey\n-----END PRIVATE KEY-----',
+	};
+
+	const requestOptions: IHttpRequestOptions = {
+		headers: {},
+		method: 'GET',
+		url: 'https://login.salesforce.com/services/data/v59.0',
+	};
+
+	beforeEach(() => {
+		mockedAxios.mockReset();
+		mockedAxios.mockResolvedValue({ data: { access_token: 'abc123' } });
+		mockedSign.mockReset();
+		mockedSign.mockReturnValue('signed-jwt');
+	});
+
+	it('should have correct properties', () => {
+		expect(credential.name).toBe('salesforceJwtApi');
+		expect(credential.displayName).toBe('Salesforce JWT API');
+		expect(credential.documentationUrl).toBe('salesforce');
+		expect(credential.test.request.baseURL).toBe(
+			'={{$credentials?.myDomainUrl ? $credentials.myDomainUrl.replace(/\\/$/, "") : ($credentials?.environment === "sandbox" ? "https://test.salesforce.com" : "https://login.salesforce.com")}}',
+		);
+		expect(credential.test.request.url).toBe('/services/oauth2/userinfo');
+	});
+
+	describe('resolveAuthUrl', () => {
+		it('defaults to login.salesforce.com for production when My Domain URL is empty', () => {
+			expect(
+				resolveAuthUrl({ ...baseCredentials, environment: 'production', myDomainUrl: '' }),
+			).toBe('https://login.salesforce.com');
+		});
+
+		it('defaults to test.salesforce.com for sandbox when My Domain URL is empty', () => {
+			expect(resolveAuthUrl({ ...baseCredentials, environment: 'sandbox', myDomainUrl: '' })).toBe(
+				'https://test.salesforce.com',
+			);
+		});
+
+		it('falls back to the default when My Domain URL is missing', () => {
+			expect(resolveAuthUrl({ ...baseCredentials, environment: 'production' })).toBe(
+				'https://login.salesforce.com',
+			);
+		});
+
+		it('uses the My Domain URL override when provided', () => {
+			expect(
+				resolveAuthUrl({
+					...baseCredentials,
+					environment: 'production',
+					myDomainUrl: 'https://acme.my.salesforce.com',
+				}),
+			).toBe('https://acme.my.salesforce.com');
+		});
+
+		it('strips a trailing slash from the My Domain URL', () => {
+			expect(
+				resolveAuthUrl({
+					...baseCredentials,
+					environment: 'sandbox',
+					myDomainUrl: 'https://acme--sandbox.sandbox.my.salesforce.com/',
+				}),
+			).toBe('https://acme--sandbox.sandbox.my.salesforce.com');
+		});
+
+		it('prefers the My Domain URL over the environment setting', () => {
+			expect(
+				resolveAuthUrl({
+					...baseCredentials,
+					environment: 'sandbox',
+					myDomainUrl: 'https://acme.my.salesforce.com',
+				}),
+			).toBe('https://acme.my.salesforce.com');
+		});
+	});
+
+	describe('authenticate', () => {
+		it('signs the JWT with the sandbox default audience when no My Domain URL is set', async () => {
+			await credential.authenticate(
+				{ ...baseCredentials, environment: 'sandbox', myDomainUrl: '' },
+				requestOptions,
+			);
+
+			expect(mockedSign).toHaveBeenCalledWith(
+				expect.objectContaining({ aud: 'https://test.salesforce.com' }),
+				expect.any(String),
+				expect.any(Object),
+			);
+			expect(mockedAxios).toHaveBeenCalledWith(
+				expect.objectContaining({
+					url: 'https://test.salesforce.com/services/oauth2/token',
+				}),
+			);
+		});
+
+		it('signs the JWT with the production default audience when no My Domain URL is set', async () => {
+			await credential.authenticate(
+				{ ...baseCredentials, environment: 'production', myDomainUrl: '' },
+				requestOptions,
+			);
+
+			expect(mockedSign).toHaveBeenCalledWith(
+				expect.objectContaining({ aud: 'https://login.salesforce.com' }),
+				expect.any(String),
+				expect.any(Object),
+			);
+			expect(mockedAxios).toHaveBeenCalledWith(
+				expect.objectContaining({
+					url: 'https://login.salesforce.com/services/oauth2/token',
+				}),
+			);
+		});
+
+		it("signs the JWT with the Spring '26 sandbox My Domain URL as audience (issue #28990)", async () => {
+			await credential.authenticate(
+				{
+					...baseCredentials,
+					environment: 'sandbox',
+					myDomainUrl: 'https://acme--sandbox.sandbox.my.salesforce.com',
+				},
+				requestOptions,
+			);
+
+			expect(mockedSign).toHaveBeenCalledWith(
+				expect.objectContaining({ aud: 'https://acme--sandbox.sandbox.my.salesforce.com' }),
+				expect.any(String),
+				expect.any(Object),
+			);
+			expect(mockedAxios).toHaveBeenCalledWith(
+				expect.objectContaining({
+					url: 'https://acme--sandbox.sandbox.my.salesforce.com/services/oauth2/token',
+				}),
+			);
+		});
+
+		it('signs the JWT with a production My Domain URL as audience', async () => {
+			await credential.authenticate(
+				{
+					...baseCredentials,
+					environment: 'production',
+					myDomainUrl: 'https://acme.my.salesforce.com',
+				},
+				requestOptions,
+			);
+
+			expect(mockedSign).toHaveBeenCalledWith(
+				expect.objectContaining({ aud: 'https://acme.my.salesforce.com' }),
+				expect.any(String),
+				expect.any(Object),
+			);
+			expect(mockedAxios).toHaveBeenCalledWith(
+				expect.objectContaining({
+					url: 'https://acme.my.salesforce.com/services/oauth2/token',
+				}),
+			);
+		});
+
+		it('normalizes a trailing slash in the My Domain URL before signing', async () => {
+			await credential.authenticate(
+				{
+					...baseCredentials,
+					environment: 'sandbox',
+					myDomainUrl: 'https://acme--sandbox.sandbox.my.salesforce.com/',
+				},
+				requestOptions,
+			);
+
+			expect(mockedSign).toHaveBeenCalledWith(
+				expect.objectContaining({ aud: 'https://acme--sandbox.sandbox.my.salesforce.com' }),
+				expect.any(String),
+				expect.any(Object),
+			);
+			expect(mockedAxios).toHaveBeenCalledWith(
+				expect.objectContaining({
+					url: 'https://acme--sandbox.sandbox.my.salesforce.com/services/oauth2/token',
+				}),
+			);
+		});
+
+		it('attaches the returned access token to the outgoing request', async () => {
+			const result = await credential.authenticate(
+				{ ...baseCredentials, environment: 'production', myDomainUrl: '' },
+				requestOptions,
+			);
+
+			expect(result.headers?.Authorization).toBe('Bearer abc123');
+		});
+	});
+});
diff --git a/packages/nodes-base/nodes/Salesforce/GenericFunctions.ts b/packages/nodes-base/nodes/Salesforce/GenericFunctions.ts
index 78c52bfc3bb..54f50b06e4a 100644
--- a/packages/nodes-base/nodes/Salesforce/GenericFunctions.ts
+++ b/packages/nodes-base/nodes/Salesforce/GenericFunctions.ts
@@ -4,6 +4,7 @@ import { DateTime } from 'luxon';
 import type {
 	IExecuteFunctions,
 	ILoadOptionsFunctions,
+	ICredentialDataDecryptedObject,
 	IDataObject,
 	INodePropertyOptions,
 	JsonObject,
@@ -13,6 +14,8 @@ import type {
 } from 'n8n-workflow';
 import { NodeApiError } from 'n8n-workflow';
 
+import { resolveAuthUrl } from '../../credentials/SalesforceJwtApi.credentials';
+
 function getOptions(
 	this: IExecuteFunctions | ILoadOptionsFunctions | IPollFunctions,
 	method: IHttpRequestMethods,
@@ -42,13 +45,10 @@ function getOptions(
 
 async function getAccessToken(
 	this: IExecuteFunctions | ILoadOptionsFunctions | IPollFunctions,
-	credentials: IDataObject,
+	credentials: ICredentialDataDecryptedObject,
 ): Promise<IDataObject> {
 	const now = moment().unix();
-	const authUrl =
-		credentials.environment === 'sandbox'
-			? 'https://test.salesforce.com'
-			: 'https://login.salesforce.com';
+	const authUrl = resolveAuthUrl(credentials);
 
 	const signature = jwt.sign(
 		{
diff --git a/packages/nodes-base/nodes/Salesforce/__test__/GenericFunctions.test.ts b/packages/nodes-base/nodes/Salesforce/__test__/GenericFunctions.test.ts
index 762c946d73b..537dba143f7 100644
--- a/packages/nodes-base/nodes/Salesforce/__test__/GenericFunctions.test.ts
+++ b/packages/nodes-base/nodes/Salesforce/__test__/GenericFunctions.test.ts
@@ -622,6 +622,42 @@ describe('Salesforce -> GenericFunctions', () => {
 				});
 			});
 
+			it("should use the My Domain URL as JWT audience and token endpoint when set (Spring '26)", async () => {
+				const mockCredentials = {
+					clientId: 'test-client-id',
+					username: 'test@example.com',
+					privateKey: 'mock-private-key',
+					environment: 'sandbox',
+					myDomainUrl: 'https://acme--sandbox.sandbox.my.salesforce.com',
+				};
+				const mockResponse = {
+					access_token: 'my-domain-access-token',
+					instance_url: 'https://acme--sandbox.sandbox.my.salesforce.com',
+				};
+
+				mockExecuteFunctions.getCredentials.mockResolvedValue(mockCredentials);
+				mockRequest.mockResolvedValue(mockResponse);
+				mockExecuteFunctions.logger = {
+					debug: jest.fn(),
+				} as any;
+
+				await salesforceApiRequest.call(mockExecuteFunctions, 'GET', '/test-endpoint', {}, {});
+
+				expect(mockJwt.sign as jest.Mock).toHaveBeenCalledWith(
+					expect.objectContaining({
+						aud: 'https://acme--sandbox.sandbox.my.salesforce.com',
+					}),
+					'mock-private-key',
+					expect.any(Object),
+				);
+
+				expect(mockRequest).toHaveBeenCalledWith(
+					expect.objectContaining({
+						uri: 'https://acme--sandbox.sandbox.my.salesforce.com/services/oauth2/token',
+					}),
+				);
+			});
+
 			it('should handle JWT token exchange with body and query parameters', async () => {
 				const mockCredentials = {
 					clientId: 'test-client-id',