diff --git a/site/src/pages/AgentsPage/AgentChatPage.test.ts b/site/src/pages/AgentsPage/AgentChatPage.test.ts
index 21b7853879..9a20437dfe 100644
--- a/site/src/pages/AgentsPage/AgentChatPage.test.ts
+++ b/site/src/pages/AgentsPage/AgentChatPage.test.ts
@@ -2,9 +2,11 @@ import { act, renderHook } from "@testing-library/react";
 import { createRef } from "react";
 import { beforeEach, describe, expect, it, vi } from "vitest";
 import type { ChatQueuedMessage } from "#/api/typesGenerated";
+import { MockUserOwner, MockWorkspace } from "#/testHelpers/entities";
 import {
 	draftInputStorageKeyPrefix,
 	getPersistedDraftInputValue,
+	getWorkspaceOptionsWithLinkedWorkspace,
 	restoreOptimisticRequestSnapshot,
 	runPromoteQueuedMessage,
 	submitEditAndScroll,
@@ -93,6 +95,42 @@ const createDeferred = <T>(): Deferred<T> => {
 	return { promise, resolve, reject };
 };
 
+describe("getWorkspaceOptionsWithLinkedWorkspace", () => {
+	it("includes a missing linked workspace only when the current user owns it", () => {
+		const existingWorkspace = {
+			...MockWorkspace,
+			id: "existing-workspace",
+		};
+		const ownerWorkspaceOptions = [existingWorkspace];
+		const linkedWorkspace = {
+			...MockWorkspace,
+			id: "linked-workspace",
+			owner_id: MockUserOwner.id,
+		};
+
+		expect(
+			getWorkspaceOptionsWithLinkedWorkspace(
+				ownerWorkspaceOptions,
+				linkedWorkspace,
+				MockUserOwner.id,
+			),
+		).toEqual([linkedWorkspace, existingWorkspace]);
+
+		const sharedWorkspace = {
+			...linkedWorkspace,
+			owner_id: "another-user",
+		};
+
+		expect(
+			getWorkspaceOptionsWithLinkedWorkspace(
+				ownerWorkspaceOptions,
+				sharedWorkspace,
+				MockUserOwner.id,
+			),
+		).toBe(ownerWorkspaceOptions);
+	});
+});
+
 describe("waitForPendingChatSettingsSyncs", () => {
 	it("waits for plan-mode and workspace updates before resolving", async () => {
 		const planModeUpdate = createDeferred<void>();
diff --git a/site/src/pages/AgentsPage/AgentChatPage.tsx b/site/src/pages/AgentsPage/AgentChatPage.tsx
index a6d968d8af..b4196b7280 100644
--- a/site/src/pages/AgentsPage/AgentChatPage.tsx
+++ b/site/src/pages/AgentsPage/AgentChatPage.tsx
@@ -275,6 +275,32 @@ export const filterWorkspaceOptionsByOrganization = (
 	);
 };
 
+/** @internal Exported for testing. */
+export const getWorkspaceOptionsWithLinkedWorkspace = (
+	workspaceOptions: readonly TypesGen.Workspace[],
+	workspace: TypesGen.Workspace | undefined,
+	ownerID: string,
+): readonly TypesGen.Workspace[] => {
+	if (!workspace || workspace.owner_id !== ownerID) {
+		return workspaceOptions;
+	}
+
+	const existingIndex = workspaceOptions.findIndex(
+		(candidate) => candidate.id === workspace.id,
+	);
+	if (existingIndex === -1) {
+		return [workspace, ...workspaceOptions];
+	}
+
+	if (workspaceOptions[existingIndex] === workspace) {
+		return workspaceOptions;
+	}
+
+	const nextWorkspaceOptions = [...workspaceOptions];
+	nextWorkspaceOptions[existingIndex] = workspace;
+	return nextWorkspaceOptions;
+};
+
 const buildAttachmentMediaTypes = (
 	attachments?: readonly PendingAttachment[],
 ): ReadonlyMap<string, string> | undefined => {
@@ -723,6 +749,7 @@ const AgentChatPage: FC = () => {
 		...workspaceById(workspaceId ?? ""),
 		enabled: Boolean(workspaceId),
 	});
+	const workspace = workspaceQuery.data;
 
 	const chatModelsQuery = useQuery(chatModels());
 	const chatModelConfigsQuery = useQuery(chatModelConfigs());
@@ -736,7 +763,11 @@ const AgentChatPage: FC = () => {
 	const userDebugLoggingQuery = useQuery(userChatDebugLogging());
 	const mcpServersQuery = useQuery(mcpServerConfigs());
 	const workspacesQuery = useQuery(workspaces({ q: "owner:me", limit: 0 }));
-	const workspaceOptions = workspacesQuery.data?.workspaces ?? [];
+	const workspaceOptions = getWorkspaceOptionsWithLinkedWorkspace(
+		workspacesQuery.data?.workspaces ?? [],
+		workspace,
+		currentUser.id,
+	);
 	const desktopEnabled = desktopEnabledQuery.data?.enable_desktop ?? false;
 	const debugLoggingEnabled =
 		userDebugLoggingQuery.data?.debug_logging_enabled ?? false;
@@ -835,7 +866,6 @@ const AgentChatPage: FC = () => {
 		});
 	}, [workspaceId, queryClient]);
 	const sshConfigQuery = useQuery(deploymentSSHConfig());
-	const workspace = workspaceQuery.data;
 	const workspaceAgent = getWorkspaceAgent(workspace, undefined);
 	const { proxy } = useProxy();