diff --git a/src/features/Org2Cloud/org2CloudCapabilities.test.ts b/src/features/Org2Cloud/org2CloudCapabilities.test.ts
index b19f0c09b..f94e74b3f 100644
--- a/src/features/Org2Cloud/org2CloudCapabilities.test.ts
+++ b/src/features/Org2Cloud/org2CloudCapabilities.test.ts
@@ -26,10 +26,12 @@ describe("getCloudCapabilities", () => {
     expect(await getCloudCapabilities("jwt-1")).toEqual({
       broadcastSignals: true,
       storageSegments: false,
+      homeEndpoints: false,
     });
     expect(await getCloudCapabilities("jwt-1")).toEqual({
       broadcastSignals: true,
       storageSegments: false,
+      homeEndpoints: false,
     });
     expect(rawMock).toHaveBeenCalledTimes(1);
   });
@@ -42,6 +44,20 @@ describe("getCloudCapabilities", () => {
     expect(await getCloudCapabilities("jwt-1")).toEqual({
       broadcastSignals: true,
       storageSegments: true,
+      homeEndpoints: false,
+    });
+  });
+
+  it("parses the 0007 homeEndpoints flag", async () => {
+    rawMock.mockResolvedValueOnce({
+      broadcastSignals: true,
+      storageSegments: true,
+      homeEndpoints: true,
+    });
+    expect(await getCloudCapabilities("jwt-1")).toEqual({
+      broadcastSignals: true,
+      storageSegments: true,
+      homeEndpoints: true,
     });
   });
 
@@ -50,11 +66,13 @@ describe("getCloudCapabilities", () => {
     expect(await getCloudCapabilities("jwt-1")).toEqual({
       broadcastSignals: false,
       storageSegments: false,
+      homeEndpoints: false,
     });
     rawMock.mockResolvedValueOnce({ broadcastSignals: true });
     expect(await getCloudCapabilities("jwt-1")).toEqual({
       broadcastSignals: true,
       storageSegments: false,
+      homeEndpoints: false,
     });
     expect(rawMock).toHaveBeenCalledTimes(2);
   });
@@ -63,14 +81,17 @@ describe("getCloudCapabilities", () => {
     rawMock.mockResolvedValueOnce({
       broadcastSignals: "yes",
       storageSegments: "yes",
+      homeEndpoints: "yes",
     });
     expect(await getCloudCapabilities("jwt-1")).toEqual({
       broadcastSignals: false,
       storageSegments: false,
+      homeEndpoints: false,
     });
     expect(await getCloudCapabilities("jwt-1")).toEqual({
       broadcastSignals: false,
       storageSegments: false,
+      homeEndpoints: false,
     });
     expect(rawMock).toHaveBeenCalledTimes(1);
   });
@@ -88,10 +109,12 @@ describe("getCloudCapabilities", () => {
     expect(await first).toEqual({
       broadcastSignals: true,
       storageSegments: true,
+      homeEndpoints: false,
     });
     expect(await second).toEqual({
       broadcastSignals: true,
       storageSegments: true,
+      homeEndpoints: false,
     });
     expect(rawMock).toHaveBeenCalledTimes(1);
   });
diff --git a/src/features/Org2Cloud/org2CloudCapabilities.ts b/src/features/Org2Cloud/org2CloudCapabilities.ts
index 8ddf351d8..b59d7b2e8 100644
--- a/src/features/Org2Cloud/org2CloudCapabilities.ts
+++ b/src/features/Org2Cloud/org2CloudCapabilities.ts
@@ -13,16 +13,19 @@ import { getCloudCapabilitiesRaw } from "./org2CloudClient";
 const CloudCapabilitiesWireSchema = z.object({
   broadcastSignals: z.boolean().nullish().catch(undefined),
   storageSegments: z.boolean().nullish().catch(undefined),
+  homeEndpoints: z.boolean().nullish().catch(undefined),
 });
 
 export interface CloudCapabilities {
   broadcastSignals: boolean;
   storageSegments: boolean;
+  homeEndpoints: boolean;
 }
 
 const LEGACY_CAPABILITIES: CloudCapabilities = {
   broadcastSignals: false,
   storageSegments: false,
+  homeEndpoints: false,
 };
 
 const capabilitiesByEndpoint = new Map<string, CloudCapabilities>();
@@ -48,6 +51,7 @@ export async function getCloudCapabilities(
     const capabilities: CloudCapabilities = {
       broadcastSignals: parsed.data.broadcastSignals ?? false,
       storageSegments: parsed.data.storageSegments ?? false,
+      homeEndpoints: parsed.data.homeEndpoints ?? false,
     };
     capabilitiesByEndpoint.set(endpointKey, capabilities);
     return capabilities;
diff --git a/src/features/Org2Cloud/org2CloudClient.test.ts b/src/features/Org2Cloud/org2CloudClient.test.ts
index cec273684..c68812c53 100644
--- a/src/features/Org2Cloud/org2CloudClient.test.ts
+++ b/src/features/Org2Cloud/org2CloudClient.test.ts
@@ -326,3 +326,50 @@ describe("listMyOrgs batched entitlements (0004)", () => {
     ]);
   });
 });
+
+describe("listMyOrgs homeEndpoint (0007)", () => {
+  it("carries a roster row's homeEndpoint through", async () => {
+    fetchMock.mockResolvedValueOnce(
+      jsonResponse([
+        {
+          orgId: "org-1",
+          name: "Acme",
+          role: "member",
+          homeEndpoint: "https://shard-2.supabase.co",
+        },
+      ])
+    );
+    await expect(listMyOrgs("at-1")).resolves.toEqual([
+      {
+        orgId: "org-1",
+        name: "Acme",
+        role: "member",
+        homeEndpoint: "https://shard-2.supabase.co",
+      },
+    ]);
+  });
+
+  it("omits homeEndpoint for pre-0007 rows without the key and for null", async () => {
+    fetchMock.mockResolvedValueOnce(
+      jsonResponse([
+        { orgId: "org-1", name: "Acme", role: "owner" },
+        { orgId: "org-2", name: "Beta", role: "member", homeEndpoint: null },
+      ])
+    );
+    await expect(listMyOrgs("at-1")).resolves.toEqual([
+      { orgId: "org-1", name: "Acme", role: "owner" },
+      { orgId: "org-2", name: "Beta", role: "member" },
+    ]);
+  });
+
+  it("keeps the org and drops only the homeEndpoint when the value is malformed", async () => {
+    fetchMock.mockResolvedValueOnce(
+      jsonResponse([
+        { orgId: "org-1", name: "Acme", role: "owner", homeEndpoint: 42 },
+      ])
+    );
+    await expect(listMyOrgs("at-1")).resolves.toEqual([
+      { orgId: "org-1", name: "Acme", role: "owner" },
+    ]);
+  });
+});
diff --git a/src/features/Org2Cloud/org2CloudClient.ts b/src/features/Org2Cloud/org2CloudClient.ts
index 806e3b11d..d76bd9b9e 100644
--- a/src/features/Org2Cloud/org2CloudClient.ts
+++ b/src/features/Org2Cloud/org2CloudClient.ts
@@ -219,6 +219,11 @@ const CloudOrgWireSchema = z.object({
   // to the per-org RPC for exactly that org. `.catch(undefined)` keeps a
   // malformed entitlement from failing the whole roster parse.
   entitlement: EntitlementStateWireSchema.nullish().catch(undefined),
+  // 0007 org-sharding directory hook (design §7 step 3): the Supabase origin
+  // hosting this org's data plane. null/absent (pre-0007 backends, or an org
+  // living on the active project) ⇒ the active endpoint. `.catch(undefined)`
+  // keeps a malformed value from failing the whole roster parse.
+  homeEndpoint: z.string().nullish().catch(undefined),
 });
 
 export interface CloudOrg {
@@ -226,6 +231,8 @@ export interface CloudOrg {
   name: string;
   role: CloudOrgRole;
   entitlement?: CloudEntitlementState;
+  /** 0007 directory hook; absent ⇒ the org lives on the active endpoint. */
+  homeEndpoint?: string;
 }
 
 const CloudOrgMemberWireSchema = z.object({
@@ -276,14 +283,17 @@ export async function listMyOrgs(
     }
     return null;
   }
-  return parsed.data.map(({ orgId, name, role, entitlement }) => ({
-    orgId,
-    name,
-    role,
-    ...(entitlement
-      ? { entitlement: normalizeEntitlementWire(entitlement) }
-      : {}),
-  }));
+  return parsed.data.map(
+    ({ orgId, name, role, entitlement, homeEndpoint }) => ({
+      orgId,
+      name,
+      role,
+      ...(entitlement
+        ? { entitlement: normalizeEntitlementWire(entitlement) }
+        : {}),
+      ...(homeEndpoint ? { homeEndpoint } : {}),
+    })
+  );
 }
 
 /** Members of a cloud org (`list_org_members`). `[]` on any failure. */
diff --git a/src/features/Org2Cloud/org2CloudEndpointDirectory.test.ts b/src/features/Org2Cloud/org2CloudEndpointDirectory.test.ts
new file mode 100644
index 000000000..ca431934b
--- /dev/null
+++ b/src/features/Org2Cloud/org2CloudEndpointDirectory.test.ts
@@ -0,0 +1,108 @@
+import { describe, expect, it } from "vitest";
+
+import type { CloudEndpoint } from "./config";
+import {
+  orgsGroupedByEndpoint,
+  resolveOrgEndpoint,
+} from "./org2CloudEndpointDirectory";
+
+const OFFICIAL: CloudEndpoint = {
+  webOrigin: "https://org2-cloud-infra.vercel.app",
+  supabaseUrl: "https://official.supabase.co",
+  anonKey: "anon-key",
+  isOfficial: true,
+};
+
+describe("resolveOrgEndpoint", () => {
+  it("returns the official endpoint when homeEndpoint is absent", () => {
+    expect(resolveOrgEndpoint({}, OFFICIAL)).toBe(OFFICIAL);
+  });
+
+  it("returns the official endpoint when homeEndpoint matches it", () => {
+    expect(
+      resolveOrgEndpoint(
+        { homeEndpoint: "https://official.supabase.co" },
+        OFFICIAL
+      )
+    ).toBe(OFFICIAL);
+  });
+
+  it("swaps only the supabaseUrl for a differing https origin", () => {
+    expect(
+      resolveOrgEndpoint(
+        { homeEndpoint: "https://shard-2.supabase.co" },
+        OFFICIAL
+      )
+    ).toEqual({
+      webOrigin: "https://org2-cloud-infra.vercel.app",
+      supabaseUrl: "https://shard-2.supabase.co",
+      anonKey: "anon-key",
+      isOfficial: true,
+    });
+  });
+
+  it.each([
+    "",
+    "not-a-url",
+    "http://shard-2.supabase.co",
+    "https://shard-2.supabase.co/rest/v1",
+    "https://shard-2.supabase.co/",
+    "ftp://shard-2.supabase.co",
+  ])("returns the official endpoint for garbage origin %j", (homeEndpoint) => {
+    expect(resolveOrgEndpoint({ homeEndpoint }, OFFICIAL)).toBe(OFFICIAL);
+  });
+});
+
+interface RosterOrg {
+  orgId: string;
+  name: string;
+  homeEndpoint?: string;
+}
+
+describe("orgsGroupedByEndpoint", () => {
+  it("partitions a roster by resolved home project", () => {
+    const home: RosterOrg = { orgId: "org-1", name: "Home" };
+    const homeExplicit = {
+      orgId: "org-2",
+      name: "Home explicit",
+      homeEndpoint: "https://official.supabase.co",
+    };
+    const sharded = {
+      orgId: "org-3",
+      name: "Sharded",
+      homeEndpoint: "https://shard-2.supabase.co",
+    };
+    const shardedSibling = {
+      orgId: "org-4",
+      name: "Sharded sibling",
+      homeEndpoint: "https://shard-2.supabase.co",
+    };
+    const garbage = {
+      orgId: "org-5",
+      name: "Garbage",
+      homeEndpoint: "not-a-url",
+    };
+
+    const groups = orgsGroupedByEndpoint(
+      [home, homeExplicit, sharded, shardedSibling, garbage],
+      OFFICIAL
+    );
+
+    expect([...groups.keys()]).toEqual([
+      "https://official.supabase.co",
+      "https://shard-2.supabase.co",
+    ]);
+    expect(groups.get("https://official.supabase.co")).toEqual({
+      endpoint: OFFICIAL,
+      orgs: [home, homeExplicit, garbage],
+    });
+    expect(groups.get("https://shard-2.supabase.co")).toEqual({
+      endpoint: { ...OFFICIAL, supabaseUrl: "https://shard-2.supabase.co" },
+      orgs: [sharded, shardedSibling],
+    });
+  });
+
+  it("returns an empty map for an empty roster", () => {
+    expect(orgsGroupedByEndpoint([], OFFICIAL).size).toBe(0);
+  });
+});
diff --git a/src/features/Org2Cloud/org2CloudEndpointDirectory.ts b/src/features/Org2Cloud/org2CloudEndpointDirectory.ts
new file mode 100644
index 000000000..35c91b3ab
--- /dev/null
+++ b/src/features/Org2Cloud/org2CloudEndpointDirectory.ts
@@ -0,0 +1,52 @@
+/**
+ * Org → endpoint directory resolvers (design §7 step 3, the client half of
+ * the org-sharding lever). A 0007+ `list_my_orgs` row may carry a
+ * `homeEndpoint`: the Supabase origin hosting that org's data plane. These
+ * pure helpers resolve it against the active endpoint and group a roster by
+ * home project. NOT wired into any call site yet — the hook's contract is
+ * that a future cutover flips the data and a later PR wires the routing.
+ */
+import type { CloudEndpoint } from "./config";
+
+function asHttpsOrigin(value: string | undefined): string | null {
+  if (!value) return null;
+  try {
+    const url = new URL(value);
+    if (url.protocol !== "https:" || url.origin !== value) return null;
+    return url.origin;
+  } catch {
+    return null;
+  }
+}
+
+export function resolveOrgEndpoint(
+  org: { homeEndpoint?: string },
+  official: CloudEndpoint
+): CloudEndpoint {
+  const home = asHttpsOrigin(org.homeEndpoint);
+  if (!home || home === official.supabaseUrl) return official;
+  return { ...official, supabaseUrl: home };
+}
+
+export interface OrgEndpointGroup<T extends { homeEndpoint?: string }> {
+  endpoint: CloudEndpoint;
+  orgs: T[];
+}
+
+/** Roster partitioned by resolved home project, keyed by `supabaseUrl`. */
+export function orgsGroupedByEndpoint<T extends { homeEndpoint?: string }>(
+  orgs: readonly T[],
+  official: CloudEndpoint
+): Map<string, OrgEndpointGroup<T>> {
+  const groups = new Map<string, OrgEndpointGroup<T>>();
+  for (const org of orgs) {
+    const endpoint = resolveOrgEndpoint(org, official);
+    const group = groups.get(endpoint.supabaseUrl);
+    if (group) {
+      group.orgs.push(org);
+    } else {
+      groups.set(endpoint.supabaseUrl, { endpoint, orgs: [org] });
+    }
+  }
+  return groups;
+}
diff --git a/src/features/Org2Cloud/org2CloudOrgsAtom.ts b/src/features/Org2Cloud/org2CloudOrgsAtom.ts
index 6d2ba17fc..c6ad9450d 100644
--- a/src/features/Org2Cloud/org2CloudOrgsAtom.ts
+++ b/src/features/Org2Cloud/org2CloudOrgsAtom.ts
@@ -59,6 +59,8 @@ export interface Org2CloudOrg {
   role: string;
   /** Batched entitlement from a 0004 roster listing; absent ⇒ per-org RPC. */
   entitlement?: CloudEntitlementState;
+  /** 0007 directory hook; absent ⇒ the org lives on the active endpoint. */
+  homeEndpoint?: string;
 }
 
 export interface RefetchOrg2CloudOrgsOptions {
diff --git a/src/features/Org2Cloud/org2CloudSyncClient.test.ts b/src/features/Org2Cloud/org2CloudSyncClient.test.ts
index a03f61052..76197e6f2 100644
--- a/src/features/Org2Cloud/org2CloudSyncClient.test.ts
+++ b/src/features/Org2Cloud/org2CloudSyncClient.test.ts
@@ -61,6 +61,7 @@ beforeEach(() => {
   capabilitiesMock.mockResolvedValue({
     broadcastSignals: false,
     storageSegments: false,
+    homeEndpoints: false,
   });
 });
 
@@ -258,6 +259,7 @@ describe("storage segment offload (0006)", () => {
     capabilitiesMock.mockResolvedValue({
       broadcastSignals: false,
       storageSegments: true,
+      homeEndpoints: false,
     });
   });
 
@@ -337,6 +339,7 @@ describe("storage segment offload (0006)", () => {
     capabilitiesMock.mockResolvedValue({
       broadcastSignals: false,
       storageSegments: false,
+      homeEndpoints: false,
     });
     await appendSessionEvents("jwt-1", appendInput([makeEvent("f1")], null));
     expect(fetchMock).toHaveBeenCalledTimes(1);