diff --git a/.changeset/nasty-beers-bow.md b/.changeset/nasty-beers-bow.md
new file mode 100644
index 00000000000..2fe9941da42
--- /dev/null
+++ b/.changeset/nasty-beers-bow.md
@@ -0,0 +1,5 @@
+---
+'@graphiql/toolkit': minor
+---
+
+support graphql SSE for `options.subscriptionUrl`
diff --git a/packages/graphiql-toolkit/package.json b/packages/graphiql-toolkit/package.json
index 8e3c8bcfde2..945f16d6b21 100644
--- a/packages/graphiql-toolkit/package.json
+++ b/packages/graphiql-toolkit/package.json
@@ -32,17 +32,22 @@
   "devDependencies": {
     "graphql": "^17.0.0-alpha.7",
     "graphql-ws": "^5.5.5",
+    "graphql-sse": "^2.5.3",
     "isomorphic-fetch": "^3.0.0",
     "subscriptions-transport-ws": "0.11.0",
     "tsup": "^8.2.4"
   },
   "peerDependencies": {
     "graphql": "^15.5.0 || ^16.0.0 || ^17.0.0-alpha.2",
-    "graphql-ws": ">= 4.5.0"
+    "graphql-ws": ">= 4.5.0",
+    "graphql-sse": "^2"
   },
   "peerDependenciesMeta": {
     "graphql-ws": {
       "optional": true
+    },
+    "graphql-sse": {
+      "optional": true
     }
   },
   "keywords": [
diff --git a/packages/graphiql-toolkit/src/create-fetcher/create-sse-fetcher.ts b/packages/graphiql-toolkit/src/create-fetcher/create-sse-fetcher.ts
new file mode 100644
index 00000000000..e7c5ca1c67f
--- /dev/null
+++ b/packages/graphiql-toolkit/src/create-fetcher/create-sse-fetcher.ts
@@ -0,0 +1,87 @@
+import type {
+  ClientOptions,
+  createClient as createClientType,
+  ExecutionResult,
+} from 'graphql-sse';
+import { Fetcher, FetcherParams } from './types';
+
+/**
+ * Based on https://gist.github.com/enisdenjo/d7bc1a013433502349d2763c3d2f2b79
+ */
+export async function createSseFetcher(opts: ClientOptions): Promise<Fetcher> {
+  const { createClient } =
+    process.env.USE_IMPORT === 'false'
+      ? (require('graphql-sse') as { createClient: typeof createClientType })
+      : await import('graphql-sse');
+
+  const sseClient = createClient({
+    retryAttempts: 0,
+    // @ts-expect-error
+    singleConnection: true, // or use false if you have an HTTP/2 server
+    // @ts-expect-error
+    lazy: false, // connect as soon as the page opens
+    ...opts,
+  });
+
+  function subscribe(payload: FetcherParams) {
+    let deferred: {
+      resolve: (arg: boolean) => void;
+      reject: (arg: unknown) => void;
+    };
+
+    const pending: ExecutionResult<Record<string, unknown>, unknown>[] = [];
+    let throwMe: unknown;
+    let done = false;
+
+    const dispose = sseClient.subscribe(
+      {
+        ...payload,
+        // types are different with FetcherParams
+        operationName: payload.operationName ?? undefined,
+      },
+      {
+        next(data) {
+          pending.push(data);
+          deferred?.resolve(false);
+        },
+        error(err) {
+          throwMe = err;
+          deferred?.reject(throwMe);
+        },
+        complete() {
+          done = true;
+          deferred?.resolve(true);
+        },
+      },
+    );
+
+    return {
+      [Symbol.asyncIterator]() {
+        return this;
+      },
+      async next() {
+        if (done) {
+          return { done: true, value: undefined };
+        }
+        if (throwMe) {
+          throw throwMe;
+        }
+        if (pending.length) {
+          return { value: pending.shift() };
+        }
+        return (await new Promise((resolve, reject) => {
+          deferred = { resolve, reject };
+        }))
+          ? { done: true, value: undefined }
+          : { value: pending.shift() };
+      },
+      async return() {
+        dispose();
+        return { done: true, value: undefined };
+      },
+    };
+  }
+
+  // @ts-expect-error todo: fix type
+  return subscribe;
+}
diff --git a/packages/graphiql-toolkit/src/create-fetcher/createFetcher.ts b/packages/graphiql-toolkit/src/create-fetcher/createFetcher.ts
index b90c65ee83e..e242701984c 100644
--- a/packages/graphiql-toolkit/src/create-fetcher/createFetcher.ts
+++ b/packages/graphiql-toolkit/src/create-fetcher/createFetcher.ts
@@ -6,11 +6,12 @@ import {
   isSubscriptionWithName,
   getWsFetcher,
 } from './lib';
+import { createSseFetcher } from './create-sse-fetcher';
 
 /**
- * build a GraphiQL fetcher that is:
+ * Build a GraphiQL fetcher that is:
  * - backwards compatible
- * - optionally supports graphql-ws or `
+ * - optionally supports graphql-ws or graphql-sse
  */
 export function createGraphiQLFetcher(options: CreateFetcherOptions): Fetcher {
   const httpFetch =
@@ -40,7 +41,18 @@ export function createGraphiQLFetcher(options: CreateFetcherOptions): Fetcher {
           graphQLParams.operationName || undefined,
         )
       : false;
+
     if (isSubscription) {
+      if (
+        options.subscriptionUrl &&
+        !options.subscriptionUrl.startsWith('ws')
+      ) {
+        const sseFetcher = await createSseFetcher({
+          url: options.subscriptionUrl,
+        });
+        return sseFetcher(graphQLParams);
+      }
+
       const wsFetcher = await getWsFetcher(options, fetcherOpts);
 
       if (!wsFetcher) {
diff --git a/packages/graphiql-toolkit/src/create-fetcher/types.ts b/packages/graphiql-toolkit/src/create-fetcher/types.ts
index 9ae06a67beb..82ed1d2df31 100644
--- a/packages/graphiql-toolkit/src/create-fetcher/types.ts
+++ b/packages/graphiql-toolkit/src/create-fetcher/types.ts
@@ -81,7 +81,7 @@ export interface CreateFetcherOptions {
    */
   url: string;
   /**
-   * url for websocket subscription requests
+   * url for websocket subscription requests or SSE
    */
   subscriptionUrl?: string;
   /**
diff --git a/packages/graphiql-toolkit/tsup.config.ts b/packages/graphiql-toolkit/tsup.config.ts
index a4d1c15b46f..b9e919faea4 100644
--- a/packages/graphiql-toolkit/tsup.config.ts
+++ b/packages/graphiql-toolkit/tsup.config.ts
@@ -4,7 +4,6 @@ const opts: Options = {
   entry: ['src/**/*.ts', '!**/__tests__'],
   bundle: false,
   clean: true,
-  dts: true,
   minifySyntax: true,
 };
 
@@ -17,6 +16,7 @@ export default defineConfig([
     env: {
       USE_IMPORT: 'true',
     },
+    dts: true,
   },
   {
     ...opts,
diff --git a/packages/graphiql/cypress/e2e/graphql-ws.cy.ts b/packages/graphiql/cypress/e2e/graphql-ws.cy.ts
deleted file mode 100644
index 89bb792aeb6..00000000000
--- a/packages/graphiql/cypress/e2e/graphql-ws.cy.ts
+++ /dev/null
@@ -1,20 +0,0 @@
-describe('IncrementalDelivery support via fetcher', () => {
-  describe('When operation contains @stream', () => {
-    const testSubscription = /* GraphQL */ `
-      subscription TestSubscription($delay: Int) {
-        message(delay: $delay)
-      }
-    `;
-    const mockSubscriptionSuccess = {
-      data: {
-        message: 'Zdravo',
-      },
-    };
-
-    it('Expects a subscription to resolve', () => {
-      cy.visitWithOp({ query: testSubscription, variables: { delay: 0 } });
-      cy.clickExecuteQuery();
-      cy.assertQueryResult(mockSubscriptionSuccess);
-    });
-  });
-});
diff --git a/packages/graphiql/cypress/e2e/incremental-delivery.cy.ts b/packages/graphiql/cypress/e2e/incremental-delivery.cy.ts
index 1ea0c0ed822..eb57e3fa755 100644
--- a/packages/graphiql/cypress/e2e/incremental-delivery.cy.ts
+++ b/packages/graphiql/cypress/e2e/incremental-delivery.cy.ts
@@ -19,36 +19,16 @@ describeOrSkip('IncrementalDelivery support via fetcher', () => {
     const mockStreamSuccess = {
       data: {
         streamable: [
-          {
-            text: 'Hi',
-          },
-          {
-            text: '你好',
-          },
-          {
-            text: 'Hola',
-          },
-          {
-            text: 'أهلاً',
-          },
-          {
-            text: 'Bonjour',
-          },
-          {
-            text: 'سلام',
-          },
-          {
-            text: '안녕',
-          },
-          {
-            text: 'Ciao',
-          },
-          {
-            text: 'हेलो',
-          },
-          {
-            text: 'Здорово',
-          },
+          { text: 'Hi' },
+          { text: '你好' },
+          { text: 'Hola' },
+          { text: 'أهلاً' },
+          { text: 'Bonjour' },
+          { text: 'سلام' },
+          { text: '안녕' },
+          { text: 'Ciao' },
+          { text: 'हेलो' },
+          { text: 'Здорово' },
         ],
       },
     };
@@ -141,22 +121,10 @@ describeOrSkip('IncrementalDelivery support via fetcher', () => {
           person: {
             name: 'Mark',
             friends: [
-              {
-                name: 'James',
-                age: 1000,
-              },
-              {
-                name: 'Mary',
-                age: 1000,
-              },
-              {
-                name: 'John',
-                age: 1000,
-              },
-              {
-                name: 'Patrica',
-                age: 1000,
-              },
+              { name: 'James', age: 1000 },
+              { name: 'Mary', age: 1000 },
+              { name: 'John', age: 1000 },
+              { name: 'Patrica', age: 1000 },
             ],
             age: 1000,
           },
diff --git a/packages/graphiql/cypress/e2e/ws-sse.cy.ts b/packages/graphiql/cypress/e2e/ws-sse.cy.ts
new file mode 100644
index 00000000000..916506d3aca
--- /dev/null
+++ b/packages/graphiql/cypress/e2e/ws-sse.cy.ts
@@ -0,0 +1,27 @@
+describe('IncrementalDelivery support via fetcher', () => {
+  const testSubscription = /* GraphQL */ `
+    subscription Test {
+      message
+    }
+  `;
+
+  function assertResponse() {
+    for (const message of ['Hi', 'Bonjour', 'Hola', 'Ciao', 'Zdravo']) {
+      cy.assertQueryResult({ data: { message } });
+    }
+  }
+
+  it('should work with ws', () => {
+    cy.visit(`/?query=${testSubscription}`);
+    cy.clickExecuteQuery();
+    assertResponse();
+  });
+
+  it('should work with sse', () => {
+    cy.visit(
+      `/?subscriptionUrl=http://localhost:8080/graphql/stream&query=${testSubscription}`,
+    );
+    cy.clickExecuteQuery();
+    assertResponse();
+  });
+});
diff --git a/packages/graphiql/resources/renderExample.js b/packages/graphiql/resources/renderExample.js
index 0bbadd29069..7b42b47a1a8 100644
--- a/packages/graphiql/resources/renderExample.js
+++ b/packages/graphiql/resources/renderExample.js
@@ -77,7 +77,8 @@ root.render(
   React.createElement(GraphiQL, {
     fetcher: GraphiQL.createFetcher({
       url: getSchemaUrl(),
-      subscriptionUrl: 'ws://localhost:8081/subscriptions',
+      subscriptionUrl:
+        parameters.subscriptionUrl || 'ws://localhost:8081/subscriptions',
     }),
     query: parameters.query,
     variables: parameters.variables,
diff --git a/packages/graphiql/test/e2e-server.js b/packages/graphiql/test/e2e-server.js
index 970b8144162..7436e063f7d 100644
--- a/packages/graphiql/test/e2e-server.js
+++ b/packages/graphiql/test/e2e-server.js
@@ -17,6 +17,8 @@ const {
 const WebSocketsServer = require('./afterDevServer');
 const schema = require('./schema');
 const { customExecute } = require('./execute');
+// eslint-disable-next-line import-x/no-extraneous-dependencies
+const { createHandler } = require('graphql-sse/lib/use/express');
 
 const app = express();
 
@@ -42,6 +44,33 @@ async function handler(req, res) {
   sendResult(result, res);
 }
 
+app.use('/graphql/stream', (req, res, next) => {
+  // Fixes
+  // Access to fetch at 'http://localhost:8080/graphql/stream' from origin 'http://localhost:5173' has been blocked by
+  // CORS policy: Response to preflight request doesn't pass access control check: No 'Access-Control-Allow-Origin'
+  // header is present on the requested resource. If an opaque response serves your needs, set the request's mode to
+  // 'no-cors' to fetch the resource with CORS disabled.
+
+  // CORS headers
+  res.header('Access-Control-Allow-Origin', '*'); // restrict it to the required domain
+  res.header('Access-Control-Allow-Methods', 'GET,PUT,POST');
+  // Set custom headers for CORS
+  res.header(
+    'Access-Control-Allow-Headers',
+    'content-type,x-graphql-event-stream-token',
+  );
+
+  if (req.method === 'OPTIONS') {
+    return res.status(200).end();
+  }
+  next();
+});
+
+// Create the GraphQL over SSE handler
+const sseHandler = createHandler({ schema, execute: customExecute });
+// Serve all methods on `/graphql/stream`
+app.use('/graphql/stream', sseHandler);
+
 // Server
 app.use(express.json());
 
diff --git a/packages/graphiql/test/schema.js b/packages/graphiql/test/schema.js
index d6c048e5514..ad65af8e939 100644
--- a/packages/graphiql/test/schema.js
+++ b/packages/graphiql/test/schema.js
@@ -382,7 +382,7 @@ const TestSubscriptionType = new GraphQLObjectType({
       },
       async *subscribe(root, args) {
         for (const hi of ['Hi', 'Bonjour', 'Hola', 'Ciao', 'Zdravo']) {
-          if (args?.delay) {
+          if (args.delay) {
             await sleep(args.delay);
           }
           yield { message: hi };
diff --git a/packages/monaco-graphql/test/monaco-editor.test.ts b/packages/monaco-graphql/test/monaco-editor.test.ts
index b9fc918b879..52ea84e5a49 100644
--- a/packages/monaco-graphql/test/monaco-editor.test.ts
+++ b/packages/monaco-graphql/test/monaco-editor.test.ts
@@ -15,7 +15,7 @@ describe('monaco-editor', () => {
     // expect(lines[1]).toMatch(' building for production...');
     // expect(lines[2]).toBe('transforming...');
     expect(lines[3]).toMatch(
-      `✓ ${parseInt(version, 10) > 16 ? 862 : 843} modules transformed.`,
+      `✓ ${parseInt(version, 10) > 16 ? 869 : 843} modules transformed.`,
     );
     // expect(lines[4]).toBe('rendering chunks...');
     // expect(lines[5]).toBe('computing gzip size...');
diff --git a/yarn.lock b/yarn.lock
index b47771846d7..1e5659ea156 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -10498,6 +10498,11 @@ graphql-http@^1.22.1:
   resolved "https://registry.yarnpkg.com/graphql-http/-/graphql-http-1.22.1.tgz#3857ac75366e55db189cfe09ade9cc4c4f2cfd09"
   integrity sha512-4Jor+LRbA7SfSaw7dfDUs2UBzvWg3cKrykfHRgKsOIvQaLuf+QOcG2t3Mx5N9GzSNJcuqMqJWz0ta5+BryEmXg==
 
+graphql-sse@^2.5.3:
+  version "2.5.3"
+  resolved "https://registry.yarnpkg.com/graphql-sse/-/graphql-sse-2.5.3.tgz#c3557803f2db306d8ac87fd3bc089b6d4bac8353"
+  integrity sha512-5IcFW3e7fPOG7oFkK1v3X1wWtCJArQKB/H1UJeNotjy7a/9EYA5K+EiHJF1BiDSVNx7y64bd0FlDETrNBSvIHQ==
+
 graphql-subscriptions@^2.0.0:
   version "2.0.0"
   resolved "https://registry.yarnpkg.com/graphql-subscriptions/-/graphql-subscriptions-2.0.0.tgz#11ec181d475852d8aec879183e8e1eb94f2eb79a"