diff --git a/server/src/__tests__/chat-channels.integration.test.ts b/server/src/__tests__/chat-channels.integration.test.ts
index 39d9e150fe..292a036a64 100644
--- a/server/src/__tests__/chat-channels.integration.test.ts
+++ b/server/src/__tests__/chat-channels.integration.test.ts
@@ -1068,17 +1068,30 @@ describeEmbeddedPostgres("chat channel control-plane integration", () => {
       .where(and(inArray(chatConversations.companyId, companyIds), inArray(chatConversations.state, ["active", "waiting"])));
   }
 
-  async function seedCompany() {
+  const companyPrefixAttempts = 8;
+  const freshCompanyPrefix = () => `C${randomUUID().replaceAll("-", "").slice(0, 7).toUpperCase()}`;
+
+  async function seedCompany(nextIssuePrefix = freshCompanyPrefix) {
     const companyId = randomUUID();
-    fixtureCompanies.add(companyId);
     const assignedAgentId = randomUUID();
     const replacementAgentId = randomUUID();
-    await db.insert(companies).values({
-      id: companyId,
-      name: `Chat Test ${companyId.slice(0, 8)}`,
-      issuePrefix: `C${companyId.replaceAll("-", "").slice(0, 7).toUpperCase()}`,
-      requireBoardApprovalForNewAgents: false,
-    });
+    let inserted = false;
+    // Retired fixtures retain company rows. Retry only the short-prefix unique
+    // conflict; every other database error must still fail the test immediately.
+    for (let attempt = 0; attempt < companyPrefixAttempts; attempt += 1) {
+      const [company] = await db.insert(companies).values({
+        id: companyId,
+        name: `Chat Test ${companyId.slice(0, 8)}`,
+        issuePrefix: nextIssuePrefix(),
+        requireBoardApprovalForNewAgents: false,
+      }).onConflictDoNothing({ target: companies.issuePrefix }).returning({ id: companies.id });
+      if (company) {
+        inserted = true;
+        fixtureCompanies.add(companyId);
+        break;
+      }
+    }
+    if (!inserted) throw new Error(`Could not allocate a chat fixture company prefix after ${companyPrefixAttempts} attempts`);
     const now = new Date();
     await db
       .insert(authUsers)
@@ -1133,6 +1146,46 @@ describeEmbeddedPostgres("chat channel control-plane integration", () => {
     return { companyId, assignedAgentId, replacementAgentId };
   }
 
+  it("retries a colliding company fixture prefix and creates a distinct complete fixture", async () => {
+    const existing = await seedCompany();
+    const [original] = await db.select().from(companies).where(eq(companies.id, existing.companyId));
+    const candidates: string[] = [];
+    const nextPrefix = vi.fn(() => {
+      const prefix = candidates.length === 0 ? original!.issuePrefix : freshCompanyPrefix();
+      candidates.push(prefix);
+      return prefix;
+    });
+    const fixture = await seedCompany(nextPrefix);
+    const [allocated] = await db.select().from(companies).where(eq(companies.id, fixture.companyId));
+    expect(nextPrefix.mock.calls.length).toBeGreaterThanOrEqual(2);
+    expect(allocated!.issuePrefix).toBe(candidates.at(-1));
+    expect(allocated!.issuePrefix).toMatch(/^C[A-F0-9]{7}$/);
+    expect(allocated!.issuePrefix).not.toBe(original!.issuePrefix);
+    expect(fixture.companyId).not.toBe(existing.companyId);
+    expect(await db.select().from(companies).where(eq(companies.id, existing.companyId))).toEqual([original]);
+    expect((await db.select().from(agents).where(eq(agents.companyId, fixture.companyId))).map(agent => agent.id).sort())
+      .toEqual([fixture.assignedAgentId, fixture.replacementAgentId].sort());
+    expect(await db.select().from(companyMemberships).where(eq(companyMemberships.companyId, fixture.companyId)))
+      .toEqual([expect.objectContaining({ principalId: "owner-user", membershipRole: "operator" })]);
+  });
+
+  it("bounds company fixture prefix collision retries without creating a partial fixture", async () => {
+    const fixture = await seedCompany();
+    const [company] = await db.select().from(companies).where(eq(companies.id, fixture.companyId));
+    const before = await db.select({ id: companies.id }).from(companies);
+    const nextPrefix = vi.fn(() => company!.issuePrefix);
+    await expect(seedCompany(nextPrefix)).rejects.toThrow(`after ${companyPrefixAttempts} attempts`);
+    expect(nextPrefix).toHaveBeenCalledTimes(companyPrefixAttempts);
+    expect((await db.select({ id: companies.id }).from(companies)).map(row => row.id).sort())
+      .toEqual(before.map(row => row.id).sort());
+  });
+
+  it("does not retry unrelated company fixture database errors", async () => {
+    const nextPrefix = vi.fn(() => "C\0INVALID");
+    await expect(seedCompany(nextPrefix)).rejects.toMatchObject({ cause: { code: "22021" } });
+    expect(nextPrefix).toHaveBeenCalledOnce();
+  });
+
   // A truthy return is not a durable scheduler receipt. These transport tests
   // record the same exact receipt identity; real scheduling/coalescing is
   // separately exercised by durable-chat-wakeup.test.ts against heartbeat.