diff --git a/packages/db/src/seed.ts b/packages/db/src/seed.ts
index 5e33c05..3e90a9d 100644
--- a/packages/db/src/seed.ts
+++ b/packages/db/src/seed.ts
@@ -624,6 +624,63 @@ async function seedKnownUsers() {
     }
   }
 
+  // ── Client: UAT Customer ─────────────────────────────────────────────────────
+  // Only uat-customer is a real end-user who needs a clients row.
+  // uat-groomer and uat-super are staff — they have staff records, not client records.
+  const UAT_CUSTOMER_ID = "c0000001-0000-0000-0000-000000000001";
+  const [uatCustomerRow] = await db
+    .select()
+    .from(schema.clients)
+    .where(eq(schema.clients.email, "uat-customer@groombook.dev"))
+    .limit(1);
+
+  let uatCustomerClientId: string;
+  if (uatCustomerRow) {
+    uatCustomerClientId = uatCustomerRow.id;
+    console.log(`✓ UAT Customer client record already exists — skipping`);
+  } else {
+    const [created] = await db
+      .insert(schema.clients)
+      .values({
+        id: UAT_CUSTOMER_ID,
+        email: "uat-customer@groombook.dev",
+        name: "UAT Customer",
+        phone: "555-0102",
+        address: "1 UAT Lane, Test City, CA 90210",
+      })
+      .returning();
+    uatCustomerClientId = created!.id;
+    console.log(`✓ Created client 'UAT Customer' for SSO bridge`);
+  }
+
+  // ── Pets: UAT Customer's dogs ────────────────────────────────────────────────
+  const uatCustomerPets = [
+    { id: "c0000001-0000-0000-0000-000000000002", name: "UAT Pup Alpha", species: "Dog", breed: "Beagle", weight: "12.00", dob: "2022-03-10", image: "/demo-pets/dog-beagle.png" },
+    { id: "c0000001-0000-0000-0000-000000000003", name: "UAT Pup Beta",  species: "Dog", breed: "Labrador", weight: "28.00", dob: "2021-07-22", image: "/demo-pets/dog-labrador.png" },
+  ];
+  for (const pet of uatCustomerPets) {
+    const [existing] = await db
+      .select()
+      .from(schema.pets)
+      .where(eq(schema.pets.id, pet.id))
+      .limit(1);
+    if (existing) {
+      console.log(`✓ UAT Pet '${existing.name}' already exists — skipping`);
+    } else {
+      await db.insert(schema.pets).values({
+        id: pet.id,
+        clientId: uatCustomerClientId,
+        name: pet.name,
+        species: pet.species,
+        breed: pet.breed,
+        weightKg: pet.weight,
+        dateOfBirth: new Date(`${pet.dob}T00:00:00Z`),
+        image: pet.image,
+      });
+      console.log(`✓ Created UAT pet '${pet.name}'`);
+    }
+  }
+
   // ── Services: idempotent upsert using name as unique key ─────────────────────
   // UNIQUE constraint on services.name (migration 0020) must exist first.
   // Uses b0000001-... IDs to match main seed servicesDef for same-named services.
diff --git a/src/__tests__/portalSessionFromAuth.test.ts b/src/__tests__/portalSessionFromAuth.test.ts
index 8448803..960e61e 100644
--- a/src/__tests__/portalSessionFromAuth.test.ts
+++ b/src/__tests__/portalSessionFromAuth.test.ts
@@ -6,6 +6,10 @@ const CLIENT_ID = "550e8400-e29b-41d4-a716-446655440001";
 const CLIENT_EMAIL = "alice@example.com";
 const CLIENT_NAME = "Alice Smith";
 
+const UAT_CUSTOMER_ID = "c0000001-0000-0000-0000-000000000001";
+const UAT_CUSTOMER_EMAIL = "uat-customer@groombook.dev";
+const UAT_CUSTOMER_NAME = "UAT Customer";
+
 const BETTER_AUTH_SESSION = {
   user: {
     id: "auth-user-001",
@@ -163,6 +167,33 @@ describe("POST /portal/session-from-auth", () => {
     expect((insertedSession as Record<string, unknown>).reason).toBe("sso-bridge");
   });
 
+  it("returns 201 for uat-customer SSO bridge with correct clientId and clientName", async () => {
+    const uatAuthSession = {
+      user: {
+        id: "auth-user-uat-customer",
+        email: UAT_CUSTOMER_EMAIL,
+        name: UAT_CUSTOMER_NAME,
+      },
+      session: {
+        id: "ba-session-uat-customer",
+        expiresAt: new Date(Date.now() + 60 * 60 * 1000),
+      },
+    };
+    mockGetSession.mockResolvedValue(uatAuthSession);
+    mockClientRow = { id: UAT_CUSTOMER_ID, email: UAT_CUSTOMER_EMAIL, name: UAT_CUSTOMER_NAME };
+    mockStaffRow = { id: "00000000-0000-0000-0000-000000000001" };
+    const res = await app.request("/portal/session-from-auth", {
+      method: "POST",
+    });
+    expect(res.status).toBe(201);
+    const body = await res.json();
+    expect(body).toHaveProperty("sessionId");
+    expect(body.clientId).toBe(UAT_CUSTOMER_ID);
+    expect(body.clientName).toBe(UAT_CUSTOMER_NAME);
+    expect(insertedSession).not.toBeNull();
+    expect((insertedSession as Record<string, unknown>).reason).toBe("sso-bridge");
+  });
+
   it("returns 503 when auth is not configured", async () => {
     mockGetAuth.mockImplementation(() => {
       throw new Error("Auth not initialized");