diff --git a/.changeset/mean-poets-bow.md b/.changeset/mean-poets-bow.md
new file mode 100644
index 0000000000..1c4c7d93e1
--- /dev/null
+++ b/.changeset/mean-poets-bow.md
@@ -0,0 +1,6 @@
+---
+'@clerk/clerk-js': patch
+'@clerk/clerk-react': patch
+---
+
+Sync IsomorphicClerk with the clerk singleton and the LoadedClerk interface. IsomorphicClerk now extends from LoadedClerk.
diff --git a/packages/clerk-js/src/core/clerk.ts b/packages/clerk-js/src/core/clerk.ts
index f085cd0ba9..59e5b219f8 100644
--- a/packages/clerk-js/src/core/clerk.ts
+++ b/packages/clerk-js/src/core/clerk.ts
@@ -154,13 +154,13 @@ export default class Clerk implements ClerkInterface {
     version: __PKG_VERSION__,
   };
 
-  public client?: ClientResource;
-  public session?: ActiveSessionResource | null;
-  public organization?: OrganizationResource | null;
-  public user?: UserResource | null;
+  public client: ClientResource | undefined;
+  public session: ActiveSessionResource | null | undefined;
+  public organization: OrganizationResource | null | undefined;
+  public user: UserResource | null | undefined;
   public __internal_country?: string | null;
   public readonly frontendApi: string;
-  public readonly publishableKey?: string;
+  public readonly publishableKey: string | undefined;
 
   protected internal_last_error: ClerkAPIError | null = null;
 
@@ -191,6 +191,10 @@ export default class Clerk implements ClerkInterface {
     return Clerk.version;
   }
 
+  get sdkMetadata(): SDKMetadata {
+    return Clerk.sdkMetadata;
+  }
+
   get loaded(): boolean {
     return this.#isReady;
   }
diff --git a/packages/react/src/errors.ts b/packages/react/src/errors.ts
index 0e881c3de3..521817ecd7 100644
--- a/packages/react/src/errors.ts
+++ b/packages/react/src/errors.ts
@@ -30,7 +30,7 @@ export const invalidStateError =
   'Clerk: Invalid state. Feel free to submit a bug or reach out to support here: https://clerk.com/support';
 
 export const unsupportedNonBrowserDomainOrProxyUrlFunction =
-  'Clerk: Unsupported usage of domain or proxyUrl. The usage of domain or proxyUrl as function is not supported in non-browser environments.';
+  'Clerk: Unsupported usage of isSatellite, domain or proxyUrl. The usage of isSatellite, domain or proxyUrl as function is not supported in non-browser environments.';
 
 export const userProfilePageRenderedError =
   'Clerk: <UserProfile.Page /> component needs to be a direct child of `<UserProfile />` or `<UserButton />`.';
diff --git a/packages/react/src/isomorphicClerk.ts b/packages/react/src/isomorphicClerk.ts
index 9a30c028fe..bdfd174830 100644
--- a/packages/react/src/isomorphicClerk.ts
+++ b/packages/react/src/isomorphicClerk.ts
@@ -5,6 +5,7 @@ import type {
   ActiveSessionResource,
   AuthenticateWithMetamaskParams,
   BeforeEmitCallback,
+  BuildUrlWithAuthParams,
   Clerk,
   ClientResource,
   CreateOrganizationParams,
@@ -13,10 +14,16 @@ import type {
   HandleEmailLinkVerificationParams,
   HandleMagicLinkVerificationParams,
   HandleOAuthCallbackParams,
+  InstanceType,
   ListenerCallback,
+  LoadedClerk,
   OrganizationListProps,
   OrganizationMembershipResource,
+  OrganizationProfileProps,
   OrganizationResource,
+  OrganizationSwitcherProps,
+  RedirectOptions,
+  SDKMetadata,
   SetActiveParams,
   SignInProps,
   SignInRedirectOptions,
@@ -30,7 +37,6 @@ import type {
   UserProfileProps,
   UserResource,
 } from '@clerk/types';
-import type { OrganizationProfileProps, OrganizationSwitcherProps } from '@clerk/types';
 
 import { unsupportedNonBrowserDomainOrProxyUrlFunction } from './errors';
 import type {
@@ -57,10 +63,84 @@ type MethodName<T> = {
 
 type MethodCallback = () => Promise<unknown> | unknown;
 
-export default class IsomorphicClerk {
+type IsomorphicLoadedClerk = Omit<
+  LoadedClerk,
+  /**
+   * Override ClerkJS methods in order to support premountMethodCalls
+   */
+  | 'buildSignInUrl'
+  | 'buildSignUpUrl'
+  | 'buildUserProfileUrl'
+  | 'buildCreateOrganizationUrl'
+  | 'buildOrganizationProfileUrl'
+  | 'buildHomeUrl'
+  | 'buildUrlWithAuth'
+  | 'redirectWithAuth'
+  | 'redirectToSignIn'
+  | 'redirectToSignUp'
+  | 'handleRedirectCallback'
+  | 'handleUnauthenticated'
+  | 'authenticateWithMetamask'
+  | 'createOrganization'
+  | 'getOrganization'
+  | 'mountUserButton'
+  | 'mountOrganizationList'
+  | 'mountOrganizationSwitcher'
+  | 'mountOrganizationProfile'
+  | 'mountCreateOrganization'
+  | 'mountSignUp'
+  | 'mountSignIn'
+  | 'mountUserProfile'
+  | 'client'
+  | 'getOrganizationMemberships'
+> & {
+  // TODO: Align return type
+  redirectWithAuth: (...args: Parameters<Clerk['redirectWithAuth']>) => void;
+  // TODO: Align return type
+  redirectToSignIn: (options: SignInRedirectOptions) => void;
+  // TODO: Align return type
+  redirectToSignUp: (options: SignUpRedirectOptions) => void;
+  // TODO: Align return type and parms
+  handleRedirectCallback: (params: HandleOAuthCallbackParams) => void;
+  handleUnauthenticated: () => void;
+  // TODO: Align Promise unknown
+  authenticateWithMetamask: (params: AuthenticateWithMetamaskParams) => Promise<void>;
+  // TODO: Align return type (maybe not possible or correct)
+  createOrganization: (params: CreateOrganizationParams) => Promise<OrganizationResource | void>;
+  // TODO: Align return type (maybe not possible or correct)
+  getOrganization: (organizationId: string) => Promise<OrganizationResource | void>;
+
+  // TODO: Align return type
+  buildSignInUrl: (opts?: RedirectOptions) => string | void;
+  // TODO: Align return type
+  buildSignUpUrl: (opts?: RedirectOptions) => string | void;
+  // TODO: Align return type
+  buildUserProfileUrl: () => string | void;
+  // TODO: Align return type
+  buildCreateOrganizationUrl: () => string | void;
+  // TODO: Align return type
+  buildOrganizationProfileUrl: () => string | void;
+  // TODO: Align return type
+  buildHomeUrl: () => string | void;
+  // TODO: Align return type
+  buildUrlWithAuth: (to: string, opts?: BuildUrlWithAuthParams | undefined) => string | void;
+
+  // TODO: Align optional props
+  mountUserButton: (node: HTMLDivElement, props: UserButtonProps) => void;
+  mountOrganizationList: (node: HTMLDivElement, props: OrganizationListProps) => void;
+  mountOrganizationSwitcher: (node: HTMLDivElement, props: OrganizationSwitcherProps) => void;
+  mountOrganizationProfile: (node: HTMLDivElement, props: OrganizationProfileProps) => void;
+  mountCreateOrganization: (node: HTMLDivElement, props: CreateOrganizationProps) => void;
+  mountSignUp: (node: HTMLDivElement, props: SignUpProps) => void;
+  mountSignIn: (node: HTMLDivElement, props: SignInProps) => void;
+  mountUserProfile: (node: HTMLDivElement, props: UserProfileProps) => void;
+  client: ClientResource | undefined;
+
+  getOrganizationMemberships: () => Promise<OrganizationMembershipResource[] | void>;
+};
+
+export default class IsomorphicClerk implements IsomorphicLoadedClerk {
   private readonly mode: 'browser' | 'server';
-  private readonly frontendApi?: string;
-  private readonly publishableKey?: string;
   private readonly options: IsomorphicClerkOptions;
   private readonly Clerk: ClerkProp;
   private clerkjs: BrowserClerk | HeadlessBrowserClerk | null = null;
@@ -83,6 +163,12 @@ export default class IsomorphicClerk {
   #loaded = false;
   #domain: DomainOrProxyUrl['domain'];
   #proxyUrl: DomainOrProxyUrl['proxyUrl'];
+  #frontendApi: string | undefined;
+  #publishableKey: string | undefined;
+
+  get publishableKey(): string | undefined {
+    return this.#publishableKey;
+  }
 
   get loaded(): boolean {
     return this.#loaded;
@@ -127,8 +213,8 @@ export default class IsomorphicClerk {
 
   constructor(options: IsomorphicClerkOptions) {
     const { Clerk = null, frontendApi, publishableKey } = options || {};
-    this.frontendApi = frontendApi;
-    this.publishableKey = publishableKey;
+    this.#frontendApi = frontendApi;
+    this.#publishableKey = publishableKey;
     this.#proxyUrl = options?.proxyUrl;
     this.#domain = options?.domain;
     this.options = options;
@@ -137,6 +223,108 @@ export default class IsomorphicClerk {
     void this.loadClerkJS();
   }
 
+  get sdkMetadata(): SDKMetadata | undefined {
+    return this.clerkjs?.sdkMetadata || this.options.sdkMetadata || undefined;
+  }
+
+  get instanceType(): InstanceType | undefined {
+    return this.clerkjs?.instanceType;
+  }
+
+  get frontendApi(): string {
+    return this.clerkjs?.frontendApi || this.#frontendApi || '';
+  }
+
+  get isStandardBrowser(): boolean {
+    return this.clerkjs?.isStandardBrowser || this.options.standardBrowser || false;
+  }
+
+  get isSatellite(): boolean {
+    // This getter can run in environments where window is not available.
+    // In those cases we should expect and use domain as a string
+    if (typeof window !== 'undefined' && window.location) {
+      return handleValueOrFn(this.options.isSatellite, new URL(window.location.href), false);
+    }
+    if (typeof this.options.isSatellite === 'function') {
+      throw new Error(unsupportedNonBrowserDomainOrProxyUrlFunction);
+    }
+    return false;
+  }
+
+  isReady = (): boolean => Boolean(this.clerkjs?.isReady());
+
+  buildSignInUrl = (opts?: RedirectOptions): string | void => {
+    const callback = () => this.clerkjs?.buildSignInUrl(opts) || '';
+    if (this.clerkjs && this.#loaded) {
+      return callback();
+    } else {
+      this.premountMethodCalls.set('buildSignInUrl', callback);
+    }
+  };
+
+  buildSignUpUrl = (opts?: RedirectOptions): string | void => {
+    const callback = () => this.clerkjs?.buildSignUpUrl(opts) || '';
+    if (this.clerkjs && this.#loaded) {
+      return callback();
+    } else {
+      this.premountMethodCalls.set('buildSignUpUrl', callback);
+    }
+  };
+
+  buildUserProfileUrl = (): string | void => {
+    const callback = () => this.clerkjs?.buildUserProfileUrl() || '';
+    if (this.clerkjs && this.#loaded) {
+      return callback();
+    } else {
+      this.premountMethodCalls.set('buildUserProfileUrl', callback);
+    }
+  };
+
+  buildCreateOrganizationUrl = (): string | void => {
+    const callback = () => this.clerkjs?.buildCreateOrganizationUrl() || '';
+    if (this.clerkjs && this.#loaded) {
+      return callback();
+    } else {
+      this.premountMethodCalls.set('buildCreateOrganizationUrl', callback);
+    }
+  };
+
+  buildOrganizationProfileUrl = (): string | void => {
+    const callback = () => this.clerkjs?.buildOrganizationProfileUrl() || '';
+    if (this.clerkjs && this.#loaded) {
+      return callback();
+    } else {
+      this.premountMethodCalls.set('buildOrganizationProfileUrl', callback);
+    }
+  };
+
+  buildHomeUrl = (): string | void => {
+    const callback = () => this.clerkjs?.buildHomeUrl() || '';
+    if (this.clerkjs && this.#loaded) {
+      return callback();
+    } else {
+      this.premountMethodCalls.set('buildHomeUrl', callback);
+    }
+  };
+
+  buildUrlWithAuth = (to: string, opts?: BuildUrlWithAuthParams | undefined): string | void => {
+    const callback = () => this.clerkjs?.buildUrlWithAuth(to, opts) || '';
+    if (this.clerkjs && this.#loaded) {
+      return callback();
+    } else {
+      this.premountMethodCalls.set('buildUrlWithAuth', callback);
+    }
+  };
+
+  handleUnauthenticated = (): void => {
+    const callback = () => this.clerkjs?.handleUnauthenticated();
+    if (this.clerkjs && this.#loaded) {
+      void callback();
+    } else {
+      this.premountMethodCalls.set('handleUnauthenticated', callback);
+    }
+  };
+
   async loadClerkJS(): Promise<HeadlessBrowserClerk | BrowserClerk | undefined> {
     if (this.mode !== 'browser' || this.#loaded) {
       return;
diff --git a/packages/types/src/clerk.ts b/packages/types/src/clerk.ts
index 044d1b936a..6f9ed2c406 100644
--- a/packages/types/src/clerk.ts
+++ b/packages/types/src/clerk.ts
@@ -60,14 +60,17 @@ export interface Clerk {
   /**
    * Clerk SDK version number.
    */
-  version?: string;
+  version: string | undefined;
 
   /**
    * If present, contains information about the SDK that the host application is using.
    * For example, if Clerk is loaded through `@clerk/nextjs`, this would be `{ name: '@clerk/nextjs', version: '1.0.0' }`
    */
-  sdkMetadata?: SDKMetadata;
+  sdkMetadata: SDKMetadata | undefined;
 
+  /**
+   * If true the bootstrapping of Clerk.load() has completed successfully.
+   */
   loaded: boolean;
 
   /**
@@ -77,10 +80,10 @@ export interface Clerk {
   frontendApi: string;
 
   /** Clerk Publishable Key string. */
-  publishableKey?: string;
+  publishableKey: string | undefined;
 
   /** Clerk Proxy url string. */
-  proxyUrl?: string;
+  proxyUrl: string | undefined;
 
   /** Clerk Satellite Frontend API string. */
   domain: string;
@@ -89,22 +92,22 @@ export interface Clerk {
   isSatellite: boolean;
 
   /** Clerk Instance type is defined from the Publishable key */
-  instanceType?: InstanceType;
+  instanceType: InstanceType | undefined;
 
   /** Clerk flag for loading Clerk in a standard browser setup */
-  isStandardBrowser?: boolean;
+  isStandardBrowser: boolean | undefined;
 
   /** Client handling most Clerk operations. */
-  client?: ClientResource;
+  client: ClientResource | undefined;
 
   /** Active Session. */
-  session?: ActiveSessionResource | null;
+  session: ActiveSessionResource | null | undefined;
 
   /** Active Organization */
-  organization?: OrganizationResource | null;
+  organization: OrganizationResource | null | undefined;
 
   /** Current User. */
-  user?: UserResource | null;
+  user: UserResource | null | undefined;
 
   /**
    * Signs out the current user on single-session instances, or all users on multi-session instances
@@ -790,8 +793,8 @@ export type UserButtonProps = {
    */
   showName?: boolean;
   /**
-     Controls the default state of the UserButton
-     */
+   * Controls the default state of the UserButton
+   */
   defaultOpen?: boolean;
   /**
    * Full URL or path to navigate after sign out is complete
@@ -851,8 +854,8 @@ type LooseExtractedParams<T extends string> = `:${T}` | (string & NonNullable<un
 
 export type OrganizationSwitcherProps = {
   /**
-     Controls the default state of the OrganizationSwitcher
-     */
+   * Controls the default state of the OrganizationSwitcher
+   */
   defaultOpen?: boolean;
   /**
    * By default, users can switch between organization and their personal account.