diff --git a/.changeset/remove-chips-build-variant.md b/.changeset/remove-chips-build-variant.md
new file mode 100644
index 00000000000..1e3fcc55808
--- /dev/null
+++ b/.changeset/remove-chips-build-variant.md
@@ -0,0 +1,6 @@
+---
+"@clerk/clerk-js": patch
+"@clerk/shared": patch
+---
+
+Remove CHIPS build variant and use `partitioned_cookies` environment flag from the Clerk API to control partitioned cookie behavior at runtime.
diff --git a/packages/clerk-js/package.json b/packages/clerk-js/package.json
index 4e9c586748e..74ce6b269e2 100644
--- a/packages/clerk-js/package.json
+++ b/packages/clerk-js/package.json
@@ -42,7 +42,6 @@
     "bundlewatch:fix": "node bundlewatch-fix.mjs",
     "clean": "rimraf ./dist",
     "dev": "rspack serve --config rspack.config.js",
-    "dev:chips": "rspack serve --config rspack.config.js --env variant=\"clerk.chips.browser\"",
     "dev:headless": "rspack serve --config rspack.config.js --env variant=\"clerk.headless.browser\"",
     "dev:origin": "rspack serve --config rspack.config.js --env devOrigin=http://localhost:${PORT:-4000}",
     "dev:sandbox": "rspack serve --config rspack.config.js --env devOrigin=http://localhost:${PORT:-4000} --env sandbox=1",
diff --git a/packages/clerk-js/rspack.config.js b/packages/clerk-js/rspack.config.js
index ff22955e6f7..e2634a6440e 100644
--- a/packages/clerk-js/rspack.config.js
+++ b/packages/clerk-js/rspack.config.js
@@ -16,7 +16,6 @@ const variants = {
   clerkHeadless: 'clerk.headless',
   clerkHeadlessBrowser: 'clerk.headless.browser',
   clerkLegacyBrowser: 'clerk.legacy.browser',
-  clerkCHIPS: 'clerk.chips.browser',
 };
 
 const variantToSourceFile = {
@@ -26,7 +25,6 @@ const variantToSourceFile = {
   [variants.clerkHeadless]: './src/index.headless.ts',
   [variants.clerkHeadlessBrowser]: './src/index.headless.browser.ts',
   [variants.clerkLegacyBrowser]: './src/index.legacy.browser.ts',
-  [variants.clerkCHIPS]: './src/index.browser.ts',
 };
 
 /**
@@ -58,7 +56,6 @@ const common = ({ mode, variant, disableRHC = false }) => {
          */
         __BUILD_FLAG_KEYLESS_UI__: isDevelopment(mode),
         __BUILD_DISABLE_RHC__: JSON.stringify(disableRHC),
-        __BUILD_VARIANT_CHIPS__: variant === variants.clerkCHIPS,
       }),
       new rspack.EnvironmentPlugin({
         CLERK_ENV: mode,
@@ -447,13 +444,6 @@ const prodConfig = ({ mode, env, analysis }) => {
     // externalsForHeadless(),
   );
 
-  const clerkCHIPS = merge(
-    entryForVariant(variants.clerkCHIPS),
-    common({ mode, variant: variants.clerkCHIPS }),
-    commonForProd(),
-    commonForProdChunked(),
-  );
-
   const clerkEsm = merge(
     entryForVariant(variants.clerk),
     common({ mode, variant: variants.clerk }),
@@ -567,7 +557,6 @@ const prodConfig = ({ mode, env, analysis }) => {
     clerkLegacyBrowser,
     clerkHeadless,
     clerkHeadlessBrowser,
-    clerkCHIPS,
     clerkEsm,
     clerkEsmNoRHC,
     clerkCjs,
@@ -670,11 +659,6 @@ const devConfig = ({ mode, env }) => {
       commonForDev(),
       // externalsForHeadless(),
     ),
-    [variants.clerkCHIPS]: merge(
-      entryForVariant(variants.clerkCHIPS),
-      common({ mode, variant: variants.clerkCHIPS }),
-      commonForDev(),
-    ),
   };
 
   if (!entryToConfigMap[variant]) {
diff --git a/packages/clerk-js/src/core/auth/AuthCookieService.ts b/packages/clerk-js/src/core/auth/AuthCookieService.ts
index 51268dc6bcd..2773a54a9e4 100644
--- a/packages/clerk-js/src/core/auth/AuthCookieService.ts
+++ b/packages/clerk-js/src/core/auth/AuthCookieService.ts
@@ -12,6 +12,7 @@ import { debugLogger } from '@/utils/debug';
 import { clerkMissingDevBrowserJwt } from '../errors';
 import { eventBus, events } from '../events';
 import type { FapiClient } from '../fapiClient';
+import { Environment } from '../resources/Environment';
 import { createActiveContextCookie } from './cookies/activeContext';
 import type { ClientUatCookieHandler } from './cookies/clientUat';
 import { createClientUatCookie } from './cookies/clientUat';
@@ -74,16 +75,27 @@ export class AuthCookieService {
 
     eventBus.on(events.UserSignOut, () => this.handleSignOut());
 
+    // After Environment resolves, re-write dev browser cookies with correct
+    // partitioned attributes. Dev browser cookies are initially written before
+    // Environment is fetched, so they may have stale attributes.
+    eventBus.on(events.EnvironmentUpdate, () => {
+      this.devBrowser.refreshCookies();
+    });
+
     this.refreshTokenOnFocus();
     this.startPollingForToken();
 
-    this.clientUat = createClientUatCookie(cookieSuffix);
-    this.sessionCookie = createSessionCookie(cookieSuffix);
+    const cookieOptions = {
+      usePartitionedCookies: () => Environment.getInstance().partitionedCookies,
+    };
+    this.clientUat = createClientUatCookie(cookieSuffix, cookieOptions);
+    this.sessionCookie = createSessionCookie(cookieSuffix, cookieOptions);
     this.activeCookie = createActiveContextCookie();
     this.devBrowser = createDevBrowser({
       frontendApi: clerk.frontendApi,
       fapiClient,
       cookieSuffix,
+      cookieOptions,
     });
   }
 
diff --git a/packages/clerk-js/src/core/auth/__tests__/devBrowser.test.ts b/packages/clerk-js/src/core/auth/__tests__/devBrowser.test.ts
index 26fbe011864..9da60d8ba08 100644
--- a/packages/clerk-js/src/core/auth/__tests__/devBrowser.test.ts
+++ b/packages/clerk-js/src/core/auth/__tests__/devBrowser.test.ts
@@ -50,7 +50,8 @@ describe('Thrown errors', () => {
     const devBrowserHandler = createDevBrowser({
       frontendApi: 'white-koala-42.clerk.accounts.dev',
       fapiClient: mockFapiClient,
-      publishableKey: 'pk_test_d2hpdGUta29hbGEtNDIuY2xlcmsuYWNjb3VudHMuZGV2JA',
+      cookieSuffix: 'test-suffix',
+      cookieOptions: { usePartitionedCookies: () => false },
     });
 
     await expect(devBrowserHandler.setup()).rejects.toThrow(
diff --git a/packages/clerk-js/src/core/auth/cookies/__tests__/clientUat.test.ts b/packages/clerk-js/src/core/auth/cookies/__tests__/clientUat.test.ts
index 3caca7f6c33..912d8cf0d18 100644
--- a/packages/clerk-js/src/core/auth/cookies/__tests__/clientUat.test.ts
+++ b/packages/clerk-js/src/core/auth/cookies/__tests__/clientUat.test.ts
@@ -19,6 +19,7 @@ describe('createClientUatCookie', () => {
   const mockCookieSuffix = 'test-suffix';
   const mockExpires = new Date('2024-12-31');
   const mockDomain = 'test.domain';
+  const defaultOptions = { usePartitionedCookies: () => false };
   const mockSet = vi.fn();
   const mockRemove = vi.fn();
   const mockGet = vi.fn();
@@ -39,14 +40,14 @@ describe('createClientUatCookie', () => {
   });
 
   it('should create both suffixed and non-suffixed cookie handlers', () => {
-    createClientUatCookie(mockCookieSuffix);
+    createClientUatCookie(mockCookieSuffix, defaultOptions);
     expect(createCookieHandler).toHaveBeenCalledTimes(2);
     expect(createCookieHandler).toHaveBeenCalledWith('__client_uat');
     expect(createCookieHandler).toHaveBeenCalledWith('__client_uat_test-suffix');
   });
 
   it('should set cookies with correct parameters in non-cross-origin context', () => {
-    const cookieHandler = createClientUatCookie(mockCookieSuffix);
+    const cookieHandler = createClientUatCookie(mockCookieSuffix, defaultOptions);
     cookieHandler.set({
       id: 'test-client',
       updatedAt: new Date('2024-01-01'),
@@ -65,7 +66,7 @@ describe('createClientUatCookie', () => {
 
   it('should set cookies with None sameSite in cross-origin context', () => {
     (inCrossOriginIframe as ReturnType<typeof vi.fn>).mockReturnValue(true);
-    const cookieHandler = createClientUatCookie(mockCookieSuffix);
+    const cookieHandler = createClientUatCookie(mockCookieSuffix, defaultOptions);
     cookieHandler.set({
       id: 'test-client',
       updatedAt: new Date('2024-01-01'),
@@ -82,7 +83,7 @@ describe('createClientUatCookie', () => {
   });
 
   it('should set value to 0 when client is undefined', () => {
-    const cookieHandler = createClientUatCookie(mockCookieSuffix);
+    const cookieHandler = createClientUatCookie(mockCookieSuffix, defaultOptions);
     cookieHandler.set(undefined);
 
     expect(mockSet).toHaveBeenCalledWith('0', {
@@ -95,7 +96,7 @@ describe('createClientUatCookie', () => {
   });
 
   it('should set value to 0 when client has no signed in sessions', () => {
-    const cookieHandler = createClientUatCookie(mockCookieSuffix);
+    const cookieHandler = createClientUatCookie(mockCookieSuffix, defaultOptions);
     cookieHandler.set({
       id: 'test-client',
       updatedAt: new Date('2024-01-01'),
@@ -114,7 +115,7 @@ describe('createClientUatCookie', () => {
   it('should get cookie value from suffixed cookie first, then fallback to non-suffixed', () => {
     mockGet.mockImplementationOnce(() => '1234567890').mockImplementationOnce(() => '9876543210');
 
-    const cookieHandler = createClientUatCookie(mockCookieSuffix);
+    const cookieHandler = createClientUatCookie(mockCookieSuffix, defaultOptions);
     const result = cookieHandler.get();
 
     expect(result).toBe(1234567890);
@@ -123,7 +124,7 @@ describe('createClientUatCookie', () => {
   it('should return 0 when no cookie value is present', () => {
     mockGet.mockImplementationOnce(() => undefined).mockImplementationOnce(() => undefined);
 
-    const cookieHandler = createClientUatCookie(mockCookieSuffix);
+    const cookieHandler = createClientUatCookie(mockCookieSuffix, defaultOptions);
     const result = cookieHandler.get();
 
     expect(result).toBe(0);
@@ -131,7 +132,7 @@ describe('createClientUatCookie', () => {
 
   it('should set cookies with SameSite=None when the host requires it', () => {
     (requiresSameSiteNone as ReturnType<typeof vi.fn>).mockReturnValue(true);
-    const cookieHandler = createClientUatCookie(mockCookieSuffix);
+    const cookieHandler = createClientUatCookie(mockCookieSuffix, defaultOptions);
     cookieHandler.set({
       id: 'test-client',
       updatedAt: new Date('2024-01-01'),
@@ -146,4 +147,21 @@ describe('createClientUatCookie', () => {
       partitioned: false,
     });
   });
+
+  it('should set partitioned cookies when usePartitionedCookies returns true', () => {
+    const cookieHandler = createClientUatCookie(mockCookieSuffix, { usePartitionedCookies: () => true });
+    cookieHandler.set({
+      id: 'test-client',
+      updatedAt: new Date('2024-01-01'),
+      signedInSessions: ['session1'],
+    });
+
+    expect(mockSet).toHaveBeenCalledWith('1704067200', {
+      domain: mockDomain,
+      expires: mockExpires,
+      sameSite: 'None',
+      secure: true,
+      partitioned: true,
+    });
+  });
 });
diff --git a/packages/clerk-js/src/core/auth/cookies/__tests__/session.test.ts b/packages/clerk-js/src/core/auth/cookies/__tests__/session.test.ts
index 2e63ad845ee..5018fb04caf 100644
--- a/packages/clerk-js/src/core/auth/cookies/__tests__/session.test.ts
+++ b/packages/clerk-js/src/core/auth/cookies/__tests__/session.test.ts
@@ -17,6 +17,7 @@ describe('createSessionCookie', () => {
   const mockCookieSuffix = 'test-suffix';
   const mockToken = 'test-token';
   const mockExpires = new Date('2024-12-31');
+  const defaultOptions = { usePartitionedCookies: () => false };
   const mockSet = vi.fn();
   const mockRemove = vi.fn();
   const mockGet = vi.fn();
@@ -36,14 +37,14 @@ describe('createSessionCookie', () => {
   });
 
   it('should create both suffixed and non-suffixed cookie handlers', () => {
-    createSessionCookie(mockCookieSuffix);
+    createSessionCookie(mockCookieSuffix, defaultOptions);
     expect(createCookieHandler).toHaveBeenCalledTimes(2);
     expect(createCookieHandler).toHaveBeenCalledWith('__session');
     expect(createCookieHandler).toHaveBeenCalledWith('__session_test-suffix');
   });
 
   it('should set cookies with correct parameters in non-cross-origin context', () => {
-    const cookieHandler = createSessionCookie(mockCookieSuffix);
+    const cookieHandler = createSessionCookie(mockCookieSuffix, defaultOptions);
     cookieHandler.set(mockToken);
 
     expect(mockSet).toHaveBeenCalledTimes(2);
@@ -57,7 +58,7 @@ describe('createSessionCookie', () => {
 
   it('should set cookies with None sameSite in cross-origin context', () => {
     (inCrossOriginIframe as ReturnType<typeof vi.fn>).mockReturnValue(true);
-    const cookieHandler = createSessionCookie(mockCookieSuffix);
+    const cookieHandler = createSessionCookie(mockCookieSuffix, defaultOptions);
     cookieHandler.set(mockToken);
 
     expect(mockSet).toHaveBeenCalledWith(mockToken, {
@@ -69,14 +70,14 @@ describe('createSessionCookie', () => {
   });
 
   it('should remove both cookies when remove is called', () => {
-    const cookieHandler = createSessionCookie(mockCookieSuffix);
+    const cookieHandler = createSessionCookie(mockCookieSuffix, defaultOptions);
     cookieHandler.remove();
 
     expect(mockRemove).toHaveBeenCalledTimes(2);
   });
 
   it('should remove cookies with the same attributes as set', () => {
-    const cookieHandler = createSessionCookie(mockCookieSuffix);
+    const cookieHandler = createSessionCookie(mockCookieSuffix, defaultOptions);
     cookieHandler.set(mockToken);
     cookieHandler.remove();
 
@@ -102,7 +103,7 @@ describe('createSessionCookie', () => {
   it('should get cookie value from suffixed cookie first, then fallback to non-suffixed', () => {
     mockGet.mockImplementationOnce(() => 'suffixed-value').mockImplementationOnce(() => 'non-suffixed-value');
 
-    const cookieHandler = createSessionCookie(mockCookieSuffix);
+    const cookieHandler = createSessionCookie(mockCookieSuffix, defaultOptions);
     const result = cookieHandler.get();
 
     expect(result).toBe('suffixed-value');
@@ -111,7 +112,7 @@ describe('createSessionCookie', () => {
   it('should fallback to non-suffixed cookie when suffixed cookie is not present', () => {
     mockGet.mockImplementationOnce(() => undefined).mockImplementationOnce(() => 'non-suffixed-value');
 
-    const cookieHandler = createSessionCookie(mockCookieSuffix);
+    const cookieHandler = createSessionCookie(mockCookieSuffix, defaultOptions);
     const result = cookieHandler.get();
 
     expect(result).toBe('non-suffixed-value');
@@ -119,7 +120,7 @@ describe('createSessionCookie', () => {
 
   it('should set cookies with None sameSite on .replit.dev origins', () => {
     (requiresSameSiteNone as ReturnType<typeof vi.fn>).mockReturnValue(true);
-    const cookieHandler = createSessionCookie(mockCookieSuffix);
+    const cookieHandler = createSessionCookie(mockCookieSuffix, defaultOptions);
     cookieHandler.set(mockToken);
 
     expect(mockSet).toHaveBeenCalledWith(mockToken, {
@@ -129,4 +130,17 @@ describe('createSessionCookie', () => {
       partitioned: false,
     });
   });
+
+  it('should set partitioned cookies when usePartitionedCookies returns true', () => {
+    const cookieHandler = createSessionCookie(mockCookieSuffix, { usePartitionedCookies: () => true });
+    cookieHandler.set(mockToken);
+
+    expect(mockRemove).toHaveBeenCalledTimes(2);
+    expect(mockSet).toHaveBeenCalledWith(mockToken, {
+      expires: mockExpires,
+      sameSite: 'None',
+      secure: true,
+      partitioned: true,
+    });
+  });
 });
diff --git a/packages/clerk-js/src/core/auth/cookies/clientUat.ts b/packages/clerk-js/src/core/auth/cookies/clientUat.ts
index a90d5a77184..0a19c7e908b 100644
--- a/packages/clerk-js/src/core/auth/cookies/clientUat.ts
+++ b/packages/clerk-js/src/core/auth/cookies/clientUat.ts
@@ -15,13 +15,20 @@ export type ClientUatCookieHandler = {
   get: () => number;
 };
 
+export type ClientUatCookieOptions = {
+  usePartitionedCookies: () => boolean;
+};
+
 /**
  * Create a long-lived JS cookie to store the client last updated_at timestamp
  * for development instances (for production instance is set by FAPI).
  * The cookie is used as hint from the Clerk Backend packages to identify
  * if the user is authenticated or not.
  */
-export const createClientUatCookie = (cookieSuffix: string): ClientUatCookieHandler => {
+export const createClientUatCookie = (
+  cookieSuffix: string,
+  options: ClientUatCookieOptions,
+): ClientUatCookieHandler => {
   const clientUatCookie = createCookieHandler(CLIENT_UAT_COOKIE_NAME);
   const suffixedClientUatCookie = createCookieHandler(getSuffixedCookieName(CLIENT_UAT_COOKIE_NAME, cookieSuffix));
 
@@ -38,13 +45,10 @@ export const createClientUatCookie = (cookieSuffix: string): ClientUatCookieHand
      * Generally, this is handled by redirectWithAuth() being called and relying on the dev browser ID in the URL,
      * but if that isn't used we rely on this. In production, nothing is cross-domain and Lax is used when client_uat is set from FAPI.
      */
-    const sameSite = __BUILD_VARIANT_CHIPS__
-      ? 'None'
-      : inCrossOriginIframe() || requiresSameSiteNone()
-        ? 'None'
-        : 'Strict';
+    const isPartitioned = options.usePartitionedCookies();
+    const sameSite = isPartitioned || inCrossOriginIframe() || requiresSameSiteNone() ? 'None' : 'Strict';
     const secure = getSecureAttribute(sameSite);
-    const partitioned = __BUILD_VARIANT_CHIPS__ && secure;
+    const partitioned = isPartitioned && secure;
     const domain = getCookieDomain(undefined, undefined, { sameSite, secure });
 
     // '0' indicates the user is signed out
diff --git a/packages/clerk-js/src/core/auth/cookies/devBrowser.ts b/packages/clerk-js/src/core/auth/cookies/devBrowser.ts
index f7b6c6c5851..7b6807c49f1 100644
--- a/packages/clerk-js/src/core/auth/cookies/devBrowser.ts
+++ b/packages/clerk-js/src/core/auth/cookies/devBrowser.ts
@@ -13,10 +13,16 @@ export type DevBrowserCookieHandler = {
   remove: () => void;
 };
 
-const getCookieAttributes = (): { sameSite: string; secure: boolean } => {
-  const sameSite = inCrossOriginIframe() || requiresSameSiteNone() ? 'None' : 'Lax';
+export type DevBrowserCookieOptions = {
+  usePartitionedCookies: () => boolean;
+};
+
+const getCookieAttributes = (options: DevBrowserCookieOptions) => {
+  const isPartitioned = options.usePartitionedCookies();
+  const sameSite = isPartitioned || inCrossOriginIframe() || requiresSameSiteNone() ? 'None' : 'Lax';
   const secure = getSecureAttribute(sameSite);
-  return { sameSite, secure };
+  const partitioned = isPartitioned && secure;
+  return { sameSite, secure, partitioned } as const;
 };
 
 /**
@@ -25,7 +31,10 @@ const getCookieAttributes = (): { sameSite: string; secure: boolean } => {
  * The cookie is used to authenticate FAPI requests and pass
  * authentication from AP to the app.
  */
-export const createDevBrowserCookie = (cookieSuffix: string): DevBrowserCookieHandler => {
+export const createDevBrowserCookie = (
+  cookieSuffix: string,
+  options: DevBrowserCookieOptions,
+): DevBrowserCookieHandler => {
   const devBrowserCookie = createCookieHandler(DEV_BROWSER_JWT_KEY);
   const suffixedDevBrowserCookie = createCookieHandler(getSuffixedCookieName(DEV_BROWSER_JWT_KEY, cookieSuffix));
 
@@ -33,16 +42,30 @@ export const createDevBrowserCookie = (cookieSuffix: string): DevBrowserCookieHa
 
   const set = (jwt: string) => {
     const expires = addYears(Date.now(), 1);
-    const { sameSite, secure } = getCookieAttributes();
+    const { sameSite, secure, partitioned } = getCookieAttributes(options);
 
-    suffixedDevBrowserCookie.set(jwt, { expires, sameSite, secure });
-    devBrowserCookie.set(jwt, { expires, sameSite, secure });
+    // Remove old non-partitioned cookies — the browser treats partitioned and
+    // non-partitioned cookies with the same name as distinct cookies.
+    if (partitioned) {
+      suffixedDevBrowserCookie.remove();
+      devBrowserCookie.remove();
+    }
+
+    suffixedDevBrowserCookie.set(jwt, { expires, sameSite, secure, partitioned });
+    devBrowserCookie.set(jwt, { expires, sameSite, secure, partitioned });
   };
 
   const remove = () => {
-    const attributes = getCookieAttributes();
+    const attributes = getCookieAttributes(options);
     suffixedDevBrowserCookie.remove(attributes);
     devBrowserCookie.remove(attributes);
+
+    // Also remove non-partitioned variants — the browser treats partitioned and
+    // non-partitioned cookies with the same name as distinct cookies.
+    if (attributes.partitioned) {
+      suffixedDevBrowserCookie.remove();
+      devBrowserCookie.remove();
+    }
   };
 
   return {
diff --git a/packages/clerk-js/src/core/auth/cookies/session.ts b/packages/clerk-js/src/core/auth/cookies/session.ts
index abb91d54677..2e247f57976 100644
--- a/packages/clerk-js/src/core/auth/cookies/session.ts
+++ b/packages/clerk-js/src/core/auth/cookies/session.ts
@@ -14,11 +14,16 @@ export type SessionCookieHandler = {
   get: () => string | undefined;
 };
 
-const getCookieAttributes = (): { sameSite: string; secure: boolean; partitioned: boolean } => {
-  const sameSite = __BUILD_VARIANT_CHIPS__ ? 'None' : inCrossOriginIframe() || requiresSameSiteNone() ? 'None' : 'Lax';
+export type SessionCookieOptions = {
+  usePartitionedCookies: () => boolean;
+};
+
+const getCookieAttributes = (options: SessionCookieOptions) => {
+  const isPartitioned = options.usePartitionedCookies();
+  const sameSite = isPartitioned || inCrossOriginIframe() || requiresSameSiteNone() ? 'None' : 'Lax';
   const secure = getSecureAttribute(sameSite);
-  const partitioned = __BUILD_VARIANT_CHIPS__ && secure;
-  return { sameSite, secure, partitioned };
+  const partitioned = isPartitioned && secure;
+  return { sameSite, secure, partitioned } as const;
 };
 
 /**
@@ -26,24 +31,32 @@ const getCookieAttributes = (): { sameSite: string; secure: boolean; partitioned
  * The cookie is used by the Clerk backend SDKs to identify
  * the authenticated user.
  */
-export const createSessionCookie = (cookieSuffix: string): SessionCookieHandler => {
+export const createSessionCookie = (cookieSuffix: string, options: SessionCookieOptions): SessionCookieHandler => {
   const sessionCookie = createCookieHandler(SESSION_COOKIE_NAME);
   const suffixedSessionCookie = createCookieHandler(getSuffixedCookieName(SESSION_COOKIE_NAME, cookieSuffix));
 
   const remove = () => {
-    const attributes = getCookieAttributes();
+    const attributes = getCookieAttributes(options);
     sessionCookie.remove(attributes);
     suffixedSessionCookie.remove(attributes);
+
+    // Also remove non-partitioned variants — the browser treats partitioned and
+    // non-partitioned cookies with the same name as distinct cookies.
+    if (attributes.partitioned) {
+      sessionCookie.remove();
+      suffixedSessionCookie.remove();
+    }
   };
 
   const set = (token: string) => {
     const expires = addYears(Date.now(), 1);
-    const { sameSite, secure, partitioned } = getCookieAttributes();
+    const { sameSite, secure, partitioned } = getCookieAttributes(options);
 
-    // If setting Partitioned to true, remove the existing session cookies.
-    // This is to avoid conflicts with the same cookie name without Partitioned attribute.
+    // Remove old non-partitioned cookies — the browser treats partitioned and
+    // non-partitioned cookies with the same name as distinct cookies.
     if (partitioned) {
-      remove();
+      sessionCookie.remove();
+      suffixedSessionCookie.remove();
     }
 
     sessionCookie.set(token, { expires, sameSite, secure, partitioned });
diff --git a/packages/clerk-js/src/core/auth/devBrowser.ts b/packages/clerk-js/src/core/auth/devBrowser.ts
index c8a498f599d..9311e5c8d7a 100644
--- a/packages/clerk-js/src/core/auth/devBrowser.ts
+++ b/packages/clerk-js/src/core/auth/devBrowser.ts
@@ -5,6 +5,7 @@ import type { ClerkAPIErrorJSON } from '@clerk/shared/types';
 import { isDevOrStagingUrl } from '../../utils';
 import { clerkErrorDevInitFailed } from '../errors';
 import type { FapiClient } from '../fapiClient';
+import type { DevBrowserCookieOptions } from './cookies/devBrowser';
 import { createDevBrowserCookie } from './cookies/devBrowser';
 
 export interface DevBrowser {
@@ -17,16 +18,24 @@ export interface DevBrowser {
   setDevBrowserJWT(jwt: string): void;
 
   removeDevBrowserJWT(): void;
+
+  refreshCookies(): void;
 }
 
 export type CreateDevBrowserOptions = {
   frontendApi: string;
   cookieSuffix: string;
   fapiClient: FapiClient;
+  cookieOptions: DevBrowserCookieOptions;
 };
 
-export function createDevBrowser({ cookieSuffix, frontendApi, fapiClient }: CreateDevBrowserOptions): DevBrowser {
-  const devBrowserCookie = createDevBrowserCookie(cookieSuffix);
+export function createDevBrowser({
+  cookieSuffix,
+  frontendApi,
+  fapiClient,
+  cookieOptions,
+}: CreateDevBrowserOptions): DevBrowser {
+  const devBrowserCookie = createDevBrowserCookie(cookieSuffix, cookieOptions);
 
   function getDevBrowserJWT() {
     return devBrowserCookie.get();
@@ -99,11 +108,19 @@ export function createDevBrowser({ cookieSuffix, frontendApi, fapiClient }: Crea
     setDevBrowserJWT(data?.id);
   }
 
+  function refreshCookies() {
+    const jwt = getDevBrowserJWT();
+    if (jwt) {
+      setDevBrowserJWT(jwt);
+    }
+  }
+
   return {
     clear,
     setup,
     getDevBrowserJWT,
     setDevBrowserJWT,
     removeDevBrowserJWT,
+    refreshCookies,
   };
 }
diff --git a/packages/clerk-js/src/core/resources/Environment.ts b/packages/clerk-js/src/core/resources/Environment.ts
index f057787a747..b474760286e 100644
--- a/packages/clerk-js/src/core/resources/Environment.ts
+++ b/packages/clerk-js/src/core/resources/Environment.ts
@@ -22,6 +22,7 @@ export class Environment extends BaseResource implements EnvironmentResource {
   displayConfig: DisplayConfigResource = new DisplayConfig();
   maintenanceMode: boolean = false;
   clientDebugMode: boolean = false;
+  partitionedCookies: boolean = false;
   pathRoot = '/environment';
   userSettings: UserSettingsResource = new UserSettings();
   organizationSettings: OrganizationSettingsResource = new OrganizationSettings();
@@ -52,6 +53,7 @@ export class Environment extends BaseResource implements EnvironmentResource {
     this.displayConfig = new DisplayConfig(data.display_config);
     this.maintenanceMode = this.withDefault(data.maintenance_mode, this.maintenanceMode);
     this.clientDebugMode = this.withDefault(data.client_debug_mode, this.clientDebugMode);
+    this.partitionedCookies = this.withDefault(data.partitioned_cookies, this.partitionedCookies);
     this.organizationSettings = new OrganizationSettings(data.organization_settings);
     this.userSettings = new UserSettings(data.user_settings);
     this.commerceSettings = new CommerceSettings(data.commerce_settings);
@@ -94,6 +96,7 @@ export class Environment extends BaseResource implements EnvironmentResource {
       id: this.id ?? '',
       maintenance_mode: this.maintenanceMode,
       client_debug_mode: this.clientDebugMode,
+      partitioned_cookies: this.partitionedCookies,
       organization_settings: this.organizationSettings.__internal_toSnapshot(),
       user_settings: this.userSettings.__internal_toSnapshot(),
       commerce_settings: this.commerceSettings.__internal_toSnapshot(),
diff --git a/packages/clerk-js/src/global.d.ts b/packages/clerk-js/src/global.d.ts
index 7751ef82378..44ce8ced094 100644
--- a/packages/clerk-js/src/global.d.ts
+++ b/packages/clerk-js/src/global.d.ts
@@ -11,7 +11,6 @@ declare const __DEV__: boolean;
  * Build time feature flags.
  */
 declare const __BUILD_DISABLE_RHC__: string;
-declare const __BUILD_VARIANT_CHIPS__: boolean;
 
 interface Window {
   __unstable__onBeforeSetActive: (intent?: 'sign-out') => Promise<void> | void;
diff --git a/packages/clerk-js/vitest.config.mts b/packages/clerk-js/vitest.config.mts
index c74923a9bfd..75c361e1f71 100644
--- a/packages/clerk-js/vitest.config.mts
+++ b/packages/clerk-js/vitest.config.mts
@@ -26,7 +26,6 @@ export default defineConfig({
   plugins: [react({ jsxRuntime: 'automatic', jsxImportSource: '@emotion/react' }), viteSvgMockPlugin()],
   define: {
     __BUILD_DISABLE_RHC__: JSON.stringify(false),
-    __BUILD_VARIANT_CHIPS__: JSON.stringify(false),
     __PKG_NAME__: JSON.stringify('@clerk/clerk-js'),
     __PKG_VERSION__: JSON.stringify('test'),
   },
@@ -40,7 +39,6 @@ export default defineConfig({
         'src/**/*.d.ts',
         'src/**/index.ts',
         'src/**/index.browser.ts',
-        'src/**/index.chips.browser.ts',
         'src/**/index.headless.ts',
         'src/**/index.headless.browser.ts',
         'src/**/index.legacy.browser.ts',
diff --git a/packages/shared/src/types/environment.ts b/packages/shared/src/types/environment.ts
index 5a81ea75d8f..528cbafd640 100644
--- a/packages/shared/src/types/environment.ts
+++ b/packages/shared/src/types/environment.ts
@@ -22,5 +22,6 @@ export interface EnvironmentResource extends ClerkResource {
   onWindowLocationHost: () => boolean;
   maintenanceMode: boolean;
   clientDebugMode: boolean;
+  partitionedCookies: boolean;
   __internal_toSnapshot: () => EnvironmentJSONSnapshot;
 }
diff --git a/packages/shared/src/types/json.ts b/packages/shared/src/types/json.ts
index 783395c5fa9..ad2107cf069 100644
--- a/packages/shared/src/types/json.ts
+++ b/packages/shared/src/types/json.ts
@@ -90,6 +90,7 @@ export interface EnvironmentJSON extends ClerkResourceJSON {
   display_config: DisplayConfigJSON;
   maintenance_mode: boolean;
   organization_settings: OrganizationSettingsJSON;
+  partitioned_cookies?: boolean;
   user_settings: UserSettingsJSON;
   protect_config: ProtectConfigJSON;
 }