diff --git a/config.yaml.example b/config.yaml.example
index 68f0539..5e13fc3 100644
--- a/config.yaml.example
+++ b/config.yaml.example
@@ -6,6 +6,10 @@ repeater:
   # Node name for logging and identification
   node_name: "mesh-repeater-01"
 
+  # TX mode: forward | monitor | no_tx (default: forward)
+  # forward = repeat on; monitor = no repeat but companions/tenants can send; no_tx = all TX off
+  # mode: forward
+
   # Geographic location (optional)
   # Latitude in decimal degrees (-90 to 90)
   latitude: 0.0
diff --git a/repeater/engine.py b/repeater/engine.py
index dc6d413..0657f1e 100644
--- a/repeater/engine.py
+++ b/repeater/engine.py
@@ -154,9 +154,12 @@ class RepeaterHandler(BaseHandler):
 
         route_type = packet.header & PH_ROUTE_MASK
 
-        # Check if we're in monitor mode (receive only, no forwarding)
+        # TX mode: forward (repeat on), monitor (no repeat, tenants can TX), no_tx (all TX off)
         mode = self.config.get("repeater", {}).get("mode", "forward")
-        monitor_mode = mode == "monitor"
+        if mode not in ("forward", "monitor", "no_tx"):
+            mode = "forward"
+        allow_forward = mode == "forward"
+        allow_local_tx = mode != "no_tx"
 
         logger.debug(
             f"RX packet: header=0x{packet.header:02x}, payload_len={len(packet.payload or b'')}, "
@@ -179,16 +182,16 @@ class RepeaterHandler(BaseHandler):
         original_path_hashes = packet.get_path_hashes_hex()
         path_hash_size = packet.get_path_hash_size()
 
-        # Process for forwarding (skip if in monitor mode or if this is a local transmission)
+        # Process for forwarding (skip if repeat disabled or if this is a local transmission)
         result = (
             None
-            if (monitor_mode or local_transmission)
+            if (not allow_forward or local_transmission)
             else self.process_packet(processed_packet, snr)
         )
         forwarded_path_hashes = None
 
-        # For local transmissions, create a direct transmission result
-        if local_transmission and not monitor_mode:
+        # For local transmissions, create a direct transmission result (if local TX allowed)
+        if local_transmission and allow_local_tx:
             # Mark local packet as seen to prevent duplicate processing when received back
             self.mark_seen(packet)
             # Calculate transmission delay for local packets
@@ -285,9 +288,11 @@ class RepeaterHandler(BaseHandler):
                         )
         else:
             self.dropped_count += 1
-            # Determine drop reason from process_packet result
-            if monitor_mode:
-                drop_reason = "Monitor mode"
+            # Determine drop reason
+            if local_transmission and not allow_local_tx:
+                drop_reason = "No TX mode"
+            elif not allow_forward:
+                drop_reason = "Repeat disabled"
             else:
                 # Check if packet has a specific drop reason set by handlers
                 drop_reason = processed_packet.drop_reason or self._get_drop_reason(
diff --git a/repeater/handler_helpers/mesh_cli.py b/repeater/handler_helpers/mesh_cli.py
index a05bf81..78f1c0d 100644
--- a/repeater/handler_helpers/mesh_cli.py
+++ b/repeater/handler_helpers/mesh_cli.py
@@ -236,8 +236,8 @@ class MeshCLI:
             return f"> {name}"
 
         elif param == "repeat":
-            disabled = self.repeater_config.get("disable_forward", False)
-            return f"> {'off' if disabled else 'on'}"
+            mode = self.repeater_config.get("mode", "forward")
+            return f"> {'on' if mode == 'forward' else 'off'}"
 
         elif param == "lat":
             lat = self.repeater_config.get("latitude", 0.0)
@@ -353,11 +353,10 @@ class MeshCLI:
                 return "OK"
 
             elif key == "repeat":
-                disabled = value.lower() == "off"
-                self.repeater_config["disable_forward"] = disabled
+                self.repeater_config["mode"] = "forward" if value.lower() == "on" else "monitor"
                 saved, _ = self.config_manager.save_to_file()
                 self.config_manager.live_update_daemon(["repeater"])
-                return f"OK - repeat is now {'OFF' if disabled else 'ON'}"
+                return f"OK - repeat is now {'ON' if self.repeater_config['mode'] == 'forward' else 'OFF'}"
 
             elif key == "lat":
                 self.repeater_config["latitude"] = float(value)
diff --git a/repeater/handler_helpers/repeater_cli.py b/repeater/handler_helpers/repeater_cli.py
index d2c7492..58e9e3d 100644
--- a/repeater/handler_helpers/repeater_cli.py
+++ b/repeater/handler_helpers/repeater_cli.py
@@ -242,8 +242,8 @@ class MeshCLI:
             return f"> {name}"
 
         elif param == "repeat":
-            disabled = self.repeater_config.get("disable_forward", False)
-            return f"> {'off' if disabled else 'on'}"
+            mode = self.repeater_config.get("mode", "forward")
+            return f"> {'on' if mode == 'forward' else 'off'}"
 
         elif param == "lat":
             lat = self.repeater_config.get("latitude", 0.0)
@@ -350,10 +350,9 @@ class MeshCLI:
                 return "OK"
 
             elif key == "repeat":
-                disabled = value.lower() == "off"
-                self.repeater_config["disable_forward"] = disabled
+                self.repeater_config["mode"] = "forward" if value.lower() == "on" else "monitor"
                 self.save_config()
-                return f"OK - repeat is now {'OFF' if disabled else 'ON'}"
+                return f"OK - repeat is now {'ON' if self.repeater_config['mode'] == 'forward' else 'OFF'}"
 
             elif key == "lat":
                 self.repeater_config["latitude"] = float(value)
diff --git a/repeater/main.py b/repeater/main.py
index 83ae8ec..a1a3650 100644
--- a/repeater/main.py
+++ b/repeater/main.py
@@ -906,6 +906,11 @@ class RepeaterDaemon:
             logger.error("Cannot send advert: dispatcher or identity not initialized")
             return False
 
+        mode = self.config.get("repeater", {}).get("mode", "forward")
+        if mode == "no_tx":
+            logger.debug("Adverts disabled in no_tx mode")
+            return False
+
         try:
             from pymc_core.protocol import PacketBuilder
             from pymc_core.protocol.constants import ADVERT_FLAG_HAS_NAME, ADVERT_FLAG_IS_REPEATER
diff --git a/repeater/web/api_endpoints.py b/repeater/web/api_endpoints.py
index ac884f8..9e88edb 100644
--- a/repeater/web/api_endpoints.py
+++ b/repeater/web/api_endpoints.py
@@ -44,7 +44,7 @@ logger = logging.getLogger("HTTPServer")
 
 # Repeater Control
 # POST   /api/send_advert - Send repeater advertisement
-# POST   /api/set_mode {"mode": "forward|monitor"} - Set repeater mode
+# POST   /api/set_mode {"mode": "forward|monitor|no_tx"} - Set repeater mode
 # POST   /api/set_duty_cycle {"enabled": true|false} - Enable/disable duty cycle
 # POST   /api/update_duty_cycle_config {"enabled": true, "on_time": 300, "off_time": 60} - Update duty cycle config
 # POST   /api/update_radio_config - Update radio configuration
@@ -655,8 +655,8 @@ class APIEndpoints:
             self._require_post()
             data = cherrypy.request.json
             new_mode = data.get("mode", "forward")
-            if new_mode not in ["forward", "monitor"]:
-                return self._error("Invalid mode. Must be 'forward' or 'monitor'")
+            if new_mode not in ["forward", "monitor", "no_tx"]:
+                return self._error("Invalid mode. Must be 'forward', 'monitor', or 'no_tx'")
             if "repeater" not in self.config:
                 self.config["repeater"] = {}
             self.config["repeater"]["mode"] = new_mode
diff --git a/repeater/web/openapi.yaml b/repeater/web/openapi.yaml
index 9cfdc0e..1160378 100644
--- a/repeater/web/openapi.yaml
+++ b/repeater/web/openapi.yaml
@@ -414,7 +414,9 @@ paths:
     post:
       tags: [System]
       summary: Set repeater mode
-      description: Switch between forward and monitor modes
+      description: |
+        Set TX mode. forward = repeat on; monitor = no repeat but companions/tenants can send;
+        no_tx = all transmission disabled (receive-only).
       requestBody:
         required: true
         content:
@@ -425,10 +427,11 @@ paths:
               properties:
                 mode:
                   type: string
-                  enum: [forward, monitor]
+                  enum: [forward, monitor, no_tx]
                   description: |
-                    - forward: Active forwarding mode (default)
-                    - monitor: Passive monitoring only
+                    - forward: Repeat received packets; allow all local TX (default)
+                    - monitor: Do not repeat; allow local TX (companions, adverts, etc.)
+                    - no_tx: Do not repeat; no local TX (receive-only)
                   example: forward
             examples:
               forward:
@@ -437,6 +440,9 @@ paths:
               monitor:
                 value:
                   mode: monitor
+              no_tx:
+                value:
+                  mode: no_tx
       responses:
         '200':
           description: Mode changed
diff --git a/tests/test_engine.py b/tests/test_engine.py
index a4be9b4..b35b031 100644
--- a/tests/test_engine.py
+++ b/tests/test_engine.py
@@ -3,8 +3,9 @@ tests for pyMC_Repeater engine.py — RepeaterHandler.
 
 Covers: flood_forward, direct_forward, process_packet, duplicate detection,
 mark_seen, validate_packet, packet scoring, TX delay, cache management,
-airtime duty-cycle, and config reloading.
+airtime duty-cycle, TX mode (forward/monitor/no_tx), and config reloading.
 """
+import asyncio
 import copy
 import math
 import time
@@ -972,6 +973,66 @@ class TestEdgeCases:
         assert result is not None
 
 
+# ===================================================================
+# 15b. TX mode: forward, monitor, no_tx
+# ===================================================================
+
+@pytest.mark.asyncio
+class TestTxMode:
+    """forward = repeat on; monitor = no repeat, local TX allowed; no_tx = all TX off."""
+
+    async def test_forward_mode_calls_process_packet_for_rx(self, handler):
+        """In forward mode, a received packet (not local) triggers process_packet."""
+        handler.config["repeater"]["mode"] = "forward"
+        pkt = _make_flood_packet()
+        with patch.object(handler, "process_packet", wraps=handler.process_packet) as m:
+            await handler(pkt, {"snr": 0.0, "rssi": -80}, local_transmission=False)
+            m.assert_called_once()
+
+    async def test_monitor_mode_does_not_call_process_packet_for_rx(self, handler):
+        """In monitor mode, a received packet does not trigger process_packet."""
+        handler.config["repeater"]["mode"] = "monitor"
+        pkt = _make_flood_packet()
+        with patch.object(handler, "process_packet") as m:
+            await handler(pkt, {"snr": 0.0, "rssi": -80}, local_transmission=False)
+            m.assert_not_called()
+
+    async def test_no_tx_mode_does_not_call_process_packet_for_rx(self, handler):
+        """In no_tx mode, a received packet does not trigger process_packet."""
+        handler.config["repeater"]["mode"] = "no_tx"
+        pkt = _make_flood_packet()
+        with patch.object(handler, "process_packet") as m:
+            await handler(pkt, {"snr": 0.0, "rssi": -80}, local_transmission=False)
+            m.assert_not_called()
+
+    async def test_monitor_mode_allows_local_tx(self, handler):
+        """In monitor mode, local_transmission=True still schedules send_packet."""
+        handler.config["repeater"]["mode"] = "monitor"
+        pkt = _make_flood_packet()
+        with patch("repeater.engine.asyncio.sleep", new_callable=AsyncMock):
+            await handler(pkt, {"snr": 0.0, "rssi": -80}, local_transmission=True)
+            await asyncio.sleep(0)  # flush scheduled task
+        handler.dispatcher.send_packet.assert_called_once()
+
+    async def test_no_tx_mode_blocks_local_tx(self, handler):
+        """In no_tx mode, local_transmission=True does not schedule send_packet."""
+        handler.config["repeater"]["mode"] = "no_tx"
+        pkt = _make_flood_packet()
+        with patch("repeater.engine.asyncio.sleep", new_callable=AsyncMock):
+            await handler(pkt, {"snr": 0.0, "rssi": -80}, local_transmission=True)
+            await asyncio.sleep(0)
+        handler.dispatcher.send_packet.assert_not_called()
+
+    async def test_forward_mode_allows_local_tx(self, handler):
+        """In forward mode, local_transmission=True schedules send_packet."""
+        handler.config["repeater"]["mode"] = "forward"
+        pkt = _make_flood_packet()
+        with patch("repeater.engine.asyncio.sleep", new_callable=AsyncMock):
+            await handler(pkt, {"snr": 0.0, "rssi": -80}, local_transmission=True)
+            await asyncio.sleep(0)
+        handler.dispatcher.send_packet.assert_called_once()
+
+
 # ===================================================================
 # 16. Airtime calculation correctness
 # ===================================================================