diff --git a/src/db.ts b/src/db.ts
index 4668c34..706d50e 100644
--- a/src/db.ts
+++ b/src/db.ts
@@ -913,6 +913,22 @@ export function _initTestDatabaseFromFile(dbPath: string): void {
   createSchema(db);
 }
 
+/** @internal - for tests only. */
+export function _setStoredRoomOwnerAgentTypeForTests(
+  chatJid: string,
+  ownerAgentType: AgentType | null,
+): void {
+  if (!db) {
+    throw new Error('Database not initialized');
+  }
+  db.prepare(
+    `UPDATE room_settings
+     SET owner_agent_type = ?,
+         updated_at = ?
+     WHERE chat_jid = ?`,
+  ).run(ownerAgentType, new Date().toISOString(), chatJid);
+}
+
 /**
  * Store chat metadata only (no message content).
  * Used for all chats to enable group discovery without storing sensitive content.
diff --git a/src/service-routing.test.ts b/src/service-routing.test.ts
index cc918bf..0e6e766 100644
--- a/src/service-routing.test.ts
+++ b/src/service-routing.test.ts
@@ -1,6 +1,7 @@
 import { beforeEach, describe, expect, it } from 'vitest';
 
 import {
+  _setStoredRoomOwnerAgentTypeForTests,
   _initTestDatabase,
   setExplicitRoomMode,
   setRegisteredGroup,
@@ -108,6 +109,53 @@ describe('service-routing global failover', () => {
     });
   });
 
+  it('uses stored owner agent type when room_settings selects a different owner', () => {
+    setRegisteredGroup('dc:stored-owner-claude', {
+      name: 'Stored Owner Claude',
+      folder: 'stored-owner-claude',
+      trigger: '@Andy',
+      added_at: '2024-01-01T00:00:00.000Z',
+      agentType: 'claude-code',
+    });
+    setRegisteredGroup('dc:stored-owner-claude', {
+      name: 'Stored Owner Claude',
+      folder: 'stored-owner-claude',
+      trigger: '@Codex',
+      added_at: '2024-01-01T00:00:00.000Z',
+      agentType: 'codex',
+    });
+    setExplicitRoomMode('dc:stored-owner-claude', 'single');
+    _setStoredRoomOwnerAgentTypeForTests(
+      'dc:stored-owner-claude',
+      'claude-code',
+    );
+
+    expect(getEffectiveChannelLease('dc:stored-owner-claude')).toMatchObject({
+      chat_jid: 'dc:stored-owner-claude',
+      owner_service_id: 'claude',
+      reviewer_service_id: null,
+      explicit: false,
+    });
+  });
+
+  it('falls back to the available service when stored owner agent type is unavailable', () => {
+    setRegisteredGroup('dc:stored-owner-fallback', {
+      name: 'Stored Owner Fallback',
+      folder: 'stored-owner-fallback',
+      trigger: '@Andy',
+      added_at: '2024-01-01T00:00:00.000Z',
+      agentType: 'claude-code',
+    });
+    _setStoredRoomOwnerAgentTypeForTests('dc:stored-owner-fallback', 'codex');
+
+    expect(getEffectiveChannelLease('dc:stored-owner-fallback')).toMatchObject({
+      chat_jid: 'dc:stored-owner-fallback',
+      owner_service_id: 'claude',
+      reviewer_service_id: null,
+      explicit: false,
+    });
+  });
+
   it('creates a same-service reviewer lease when explicit tribunal is runnable on a solo registration', () => {
     setRegisteredGroup('dc:explicit-tribunal', {
       name: 'Explicit Tribunal Claude',
@@ -145,4 +193,13 @@ describe('service-routing global failover', () => {
       explicit: false,
     });
   });
+
+  it('keeps the legacy claude fallback for chats without room settings', () => {
+    expect(getEffectiveChannelLease('dc:unregistered')).toMatchObject({
+      chat_jid: 'dc:unregistered',
+      owner_service_id: 'claude',
+      reviewer_service_id: null,
+      explicit: false,
+    });
+  });
 });
diff --git a/src/service-routing.ts b/src/service-routing.ts
index d1b8790..9194228 100644
--- a/src/service-routing.ts
+++ b/src/service-routing.ts
@@ -14,10 +14,12 @@ import {
   getAllChannelOwnerLeases,
   getEffectiveRuntimeRoomMode,
   getRegisteredAgentTypesForJid,
+  getStoredRoomSettings,
   setChannelOwnerLease,
   type ChannelOwnerLeaseRow,
 } from './db.js';
 import { logger } from './logger.js';
+import type { AgentType } from './types.js';
 
 export interface EffectiveChannelLease {
   chat_jid: string;
@@ -55,21 +57,44 @@ function normalizeLeaseRow(
   };
 }
 
-function getDefaultLease(chatJid: string): EffectiveChannelLease {
+function getServiceIdForAgentType(agentType: AgentType): string {
+  return agentType === 'codex' ? CODEX_MAIN_SERVICE_ID : CLAUDE_SERVICE_ID;
+}
+
+function inferFallbackOwnerAgentType(
+  hasClaude: boolean,
+  hasCodex: boolean,
+): AgentType | undefined {
+  if (hasClaude && hasCodex) return OWNER_AGENT_TYPE;
+  if (hasCodex) return 'codex';
+  if (hasClaude) return 'claude-code';
+  return undefined;
+}
+
+function resolveDefaultOwnerAgentType(chatJid: string): AgentType | undefined {
   const types = getRegisteredAgentTypesForJid(chatJid);
   const hasClaude = types.includes('claude-code');
   const hasCodex = types.includes('codex');
+  const storedOwnerAgentType = getStoredRoomSettings(chatJid)?.ownerAgentType;
+
+  if (storedOwnerAgentType === 'claude-code' && hasClaude) {
+    return 'claude-code';
+  }
+  if (storedOwnerAgentType === 'codex' && hasCodex) {
+    return 'codex';
+  }
+
+  return inferFallbackOwnerAgentType(hasClaude, hasCodex);
+}
+
+function getDefaultLease(chatJid: string): EffectiveChannelLease {
   const roomMode = getEffectiveRuntimeRoomMode(chatJid);
+  const ownerAgentType = resolveDefaultOwnerAgentType(chatJid);
+  const ownerServiceId = ownerAgentType
+    ? getServiceIdForAgentType(ownerAgentType)
+    : CLAUDE_SERVICE_ID;
 
   if (roomMode === 'tribunal') {
-    const ownerServiceId =
-      hasClaude && hasCodex
-        ? OWNER_AGENT_TYPE === 'codex'
-          ? CODEX_MAIN_SERVICE_ID
-          : CLAUDE_SERVICE_ID
-        : hasCodex
-          ? CODEX_MAIN_SERVICE_ID
-          : CLAUDE_SERVICE_ID;
     return {
       chat_jid: chatJid,
       owner_service_id: ownerServiceId,
@@ -81,33 +106,9 @@ function getDefaultLease(chatJid: string): EffectiveChannelLease {
     };
   }
 
-  if (hasCodex) {
-    return {
-      chat_jid: chatJid,
-      owner_service_id: CODEX_MAIN_SERVICE_ID,
-      reviewer_service_id: null,
-      arbiter_service_id: null,
-      activated_at: null,
-      reason: null,
-      explicit: false,
-    };
-  }
-
-  if (hasClaude) {
-    return {
-      chat_jid: chatJid,
-      owner_service_id: CLAUDE_SERVICE_ID,
-      reviewer_service_id: null,
-      arbiter_service_id: null,
-      activated_at: null,
-      reason: null,
-      explicit: false,
-    };
-  }
-
   return {
     chat_jid: chatJid,
-    owner_service_id: CLAUDE_SERVICE_ID,
+    owner_service_id: ownerServiceId,
     reviewer_service_id: null,
     arbiter_service_id: null,
     activated_at: null,