diff --git a/app/radio.py b/app/radio.py
index 9dc9aa6..ed86958 100644
--- a/app/radio.py
+++ b/app/radio.py
@@ -262,10 +262,11 @@ class RadioManager:
 
                     # Apply flood scope from settings (best-effort; older firmware
                     # may not support set_flood_scope)
+                    from app.region_scope import normalize_region_scope
                     from app.repository import AppSettingsRepository
 
                     app_settings = await AppSettingsRepository.get()
-                    scope = app_settings.flood_scope
+                    scope = normalize_region_scope(app_settings.flood_scope)
                     try:
                         await mc.commands.set_flood_scope(scope if scope else "")
                         logger.info("Applied flood_scope=%r", scope or "(disabled)")
diff --git a/app/region_scope.py b/app/region_scope.py
new file mode 100644
index 0000000..681d4cf
--- /dev/null
+++ b/app/region_scope.py
@@ -0,0 +1,20 @@
+"""Helpers for normalizing MeshCore flood-scope / region names."""
+
+
+def normalize_region_scope(scope: str | None) -> str:
+    """Normalize a user-facing region scope into MeshCore's internal form.
+
+    Region names are now user-facing plain strings like ``Esperance``.
+    Internally, MeshCore still expects hashtag-style names like ``#Esperance``.
+
+    Backward compatibility:
+    - blank/None stays disabled (`""`)
+    - existing leading ``#`` is preserved
+    """
+
+    stripped = (scope or "").strip()
+    if not stripped:
+        return ""
+    if stripped.startswith("#"):
+        return stripped
+    return f"#{stripped}"
diff --git a/app/routers/channels.py b/app/routers/channels.py
index 8f3831a..f9ea589 100644
--- a/app/routers/channels.py
+++ b/app/routers/channels.py
@@ -9,6 +9,7 @@ from app.dependencies import require_connected
 from app.models import Channel, ChannelDetail, ChannelMessageCounts, ChannelTopSender
 from app.radio import radio_manager
 from app.radio_sync import upsert_channel_from_radio_slot
+from app.region_scope import normalize_region_scope
 from app.repository import ChannelRepository, MessageRepository
 from app.websocket import broadcast_event
 
@@ -153,7 +154,7 @@ async def set_channel_flood_scope_override(
     if not channel:
         raise HTTPException(status_code=404, detail="Channel not found")
 
-    override = request.flood_scope_override.strip() or None
+    override = normalize_region_scope(request.flood_scope_override) or None
     updated = await ChannelRepository.update_flood_scope_override(channel.key, override)
     if not updated:
         raise HTTPException(status_code=500, detail="Failed to update flood-scope override")
diff --git a/app/routers/messages.py b/app/routers/messages.py
index 26f8ee2..b15c960 100644
--- a/app/routers/messages.py
+++ b/app/routers/messages.py
@@ -14,6 +14,7 @@ from app.models import (
     SendDirectMessageRequest,
 )
 from app.radio import radio_manager
+from app.region_scope import normalize_region_scope
 from app.repository import AmbiguousPublicKeyPrefixError, AppSettingsRepository, MessageRepository
 from app.websocket import broadcast_error, broadcast_event
 
@@ -31,12 +32,12 @@ async def _send_channel_message_with_effective_scope(
     action_label: str,
 ) -> Any:
     """Send a channel message, temporarily overriding flood scope when configured."""
-    override_scope = (channel.flood_scope_override or "").strip()
+    override_scope = normalize_region_scope(channel.flood_scope_override)
     baseline_scope = ""
 
     if override_scope:
         settings = await AppSettingsRepository.get()
-        baseline_scope = settings.flood_scope
+        baseline_scope = normalize_region_scope(settings.flood_scope)
 
     if override_scope and override_scope != baseline_scope:
         logger.info(
diff --git a/app/routers/settings.py b/app/routers/settings.py
index 7f220a3..a5e053c 100644
--- a/app/routers/settings.py
+++ b/app/routers/settings.py
@@ -6,6 +6,7 @@ from fastapi import APIRouter
 from pydantic import BaseModel, Field
 
 from app.models import AppSettings
+from app.region_scope import normalize_region_scope
 from app.repository import AppSettingsRepository
 
 logger = logging.getLogger(__name__)
@@ -123,8 +124,7 @@ async def update_settings(update: AppSettingsUpdate) -> AppSettings:
     # Flood scope
     flood_scope_changed = False
     if update.flood_scope is not None:
-        stripped = update.flood_scope.strip()
-        kwargs["flood_scope"] = stripped
+        kwargs["flood_scope"] = normalize_region_scope(update.flood_scope)
         flood_scope_changed = True
 
     if kwargs:
diff --git a/frontend/src/components/ChatHeader.tsx b/frontend/src/components/ChatHeader.tsx
index e57fad9..5d7497d 100644
--- a/frontend/src/components/ChatHeader.tsx
+++ b/frontend/src/components/ChatHeader.tsx
@@ -2,6 +2,7 @@ import { useEffect, useState } from 'react';
 import { toast } from './ui/sonner';
 import { isFavorite } from '../utils/favorites';
 import { handleKeyboardActivate } from '../utils/a11y';
+import { stripRegionScopePrefix } from '../utils/regionScope';
 import { ContactAvatar } from './ContactAvatar';
 import { ContactStatusInfo } from './ContactStatusInfo';
 import type { Channel, Contact, Conversation, Favorite, RadioConfig } from '../types';
@@ -54,8 +55,8 @@ export function ChatHeader({
   const handleEditFloodScopeOverride = () => {
     if (conversation.type !== 'channel' || !onSetChannelFloodScopeOverride) return;
     const nextValue = window.prompt(
-      'Enter regional override flood scope for this room. This temporarily changes the radio flood scope before send and restores it after, which significantly slows room sends. Leave blank to clear.\n\nNote: some radio clients (including the official ones) implicitly add a "#" character to the beginning of a region specifier. That needs to be manually added here, so if you use the official app with region "Anytown", you should enter it here as "#Anytown".',
-      activeChannel?.flood_scope_override ?? ''
+      'Enter regional override flood scope for this room. This temporarily changes the radio flood scope before send and restores it after, which significantly slows room sends. Leave blank to clear.',
+      stripRegionScopePrefix(activeChannel?.flood_scope_override)
     );
     if (nextValue === null) return;
     onSetChannelFloodScopeOverride(conversation.id, nextValue);
@@ -140,7 +141,7 @@ export function ChatHeader({
         )}
         {conversation.type === 'channel' && activeChannel?.flood_scope_override && (
           <span className="basis-full sm:basis-auto text-[11px] text-amber-700 dark:text-amber-300 truncate">
-            Regional override active: {activeChannel.flood_scope_override}
+            Regional override active: {stripRegionScopePrefix(activeChannel.flood_scope_override)}
           </span>
         )}
         {conversation.type === 'contact' &&
diff --git a/frontend/src/components/settings/SettingsRadioSection.tsx b/frontend/src/components/settings/SettingsRadioSection.tsx
index 14f3ac7..35b748b 100644
--- a/frontend/src/components/settings/SettingsRadioSection.tsx
+++ b/frontend/src/components/settings/SettingsRadioSection.tsx
@@ -5,6 +5,7 @@ import { Button } from '../ui/button';
 import { Separator } from '../ui/separator';
 import { toast } from '../ui/sonner';
 import { RADIO_PRESETS } from '../../utils/radioPresets';
+import { stripRegionScopePrefix } from '../../utils/regionScope';
 import type {
   AppSettings,
   AppSettingsUpdate,
@@ -83,7 +84,7 @@ export function SettingsRadioSection({
 
   useEffect(() => {
     setAdvertIntervalHours(String(Math.round(appSettings.advert_interval / 3600)));
-    setFloodScope(appSettings.flood_scope);
+    setFloodScope(stripRegionScopePrefix(appSettings.flood_scope));
     setMaxRadioContacts(String(appSettings.max_radio_contacts));
   }, [appSettings]);
 
@@ -256,7 +257,7 @@ export function SettingsRadioSection({
       if (newAdvertInterval !== appSettings.advert_interval) {
         update.advert_interval = newAdvertInterval;
       }
-      if (floodScope !== appSettings.flood_scope) {
+      if (floodScope !== stripRegionScopePrefix(appSettings.flood_scope)) {
         update.flood_scope = floodScope;
       }
       const newMaxRadioContacts = parseInt(maxRadioContacts, 10);
@@ -554,10 +555,10 @@ export function SettingsRadioSection({
           id="flood-scope"
           value={floodScope}
           onChange={(e) => setFloodScope(e.target.value)}
-          placeholder="#MyRegion"
+          placeholder="MyRegion"
         />
         <p className="text-xs text-muted-foreground">
-          Tag outgoing flood messages with a region name (e.g. #MyRegion). Repeaters configured for
+          Tag outgoing flood messages with a region name (e.g. MyRegion). Repeaters configured for
           that region can forward the traffic, while repeaters configured to deny other regions may
           drop it. Leave empty to disable.
         </p>
diff --git a/frontend/src/test/chatHeaderKeyVisibility.test.tsx b/frontend/src/test/chatHeaderKeyVisibility.test.tsx
index b1e4231..04952dc 100644
--- a/frontend/src/test/chatHeaderKeyVisibility.test.tsx
+++ b/frontend/src/test/chatHeaderKeyVisibility.test.tsx
@@ -117,7 +117,7 @@ describe('ChatHeader key visibility', () => {
 
     render(<ChatHeader {...baseProps} conversation={conversation} channels={[channel]} />);
 
-    expect(screen.getByText('Regional override active: #Esperance')).toBeInTheDocument();
+    expect(screen.getByText('Regional override active: Esperance')).toBeInTheDocument();
   });
 
   it('prompts for regional override when globe button is clicked', () => {
@@ -125,7 +125,7 @@ describe('ChatHeader key visibility', () => {
     const channel = makeChannel(key, '#flightless', true);
     const conversation: Conversation = { type: 'channel', id: key, name: '#flightless' };
     const onSetChannelFloodScopeOverride = vi.fn();
-    const promptSpy = vi.spyOn(window, 'prompt').mockReturnValue('#Esperance');
+    const promptSpy = vi.spyOn(window, 'prompt').mockReturnValue('Esperance');
 
     render(
       <ChatHeader
@@ -139,7 +139,7 @@ describe('ChatHeader key visibility', () => {
     fireEvent.click(screen.getByTitle('Set regional override'));
 
     expect(promptSpy).toHaveBeenCalled();
-    expect(onSetChannelFloodScopeOverride).toHaveBeenCalledWith(key, '#Esperance');
+    expect(onSetChannelFloodScopeOverride).toHaveBeenCalledWith(key, 'Esperance');
     promptSpy.mockRestore();
   });
 });
diff --git a/frontend/src/utils/regionScope.ts b/frontend/src/utils/regionScope.ts
new file mode 100644
index 0000000..a6e3a41
--- /dev/null
+++ b/frontend/src/utils/regionScope.ts
@@ -0,0 +1,4 @@
+export function stripRegionScopePrefix(scope: string | null | undefined): string {
+  if (!scope) return '';
+  return scope.startsWith('#') ? scope.slice(1) : scope;
+}
diff --git a/tests/test_channels_router.py b/tests/test_channels_router.py
index d247e14..02aca10 100644
--- a/tests/test_channels_router.py
+++ b/tests/test_channels_router.py
@@ -270,7 +270,7 @@ class TestChannelFloodScopeOverride:
         with patch("app.routers.channels.broadcast_event") as mock_broadcast:
             response = await client.post(
                 f"/api/channels/{key}/flood-scope-override",
-                json={"flood_scope_override": "#Esperance"},
+                json={"flood_scope_override": "Esperance"},
             )
 
         assert response.status_code == 200
@@ -283,6 +283,20 @@ class TestChannelFloodScopeOverride:
         mock_broadcast.assert_called_once()
         assert mock_broadcast.call_args.args[0] == "channel"
 
+    @pytest.mark.asyncio
+    async def test_existing_hash_is_not_doubled(self, test_db, client):
+        key = "CC" * 16
+        await ChannelRepository.upsert(key=key, name="#flightless", is_hashtag=True)
+
+        response = await client.post(
+            f"/api/channels/{key}/flood-scope-override",
+            json={"flood_scope_override": "#Esperance"},
+        )
+
+        assert response.status_code == 200
+        data = response.json()
+        assert data["flood_scope_override"] == "#Esperance"
+
     @pytest.mark.asyncio
     async def test_blank_override_clears_channel_flood_scope_override(self, test_db, client):
         key = "BB" * 16
diff --git a/tests/test_radio.py b/tests/test_radio.py
index 2ff8cce..71fcf29 100644
--- a/tests/test_radio.py
+++ b/tests/test_radio.py
@@ -655,6 +655,40 @@ class TestPostConnectSetupOrdering:
 
         mock_mc.commands.set_flood_scope.assert_awaited_once_with("#TestRegion")
 
+    @pytest.mark.asyncio
+    async def test_plain_flood_scope_is_normalized_during_setup(self):
+        """Legacy/plain stored flood_scope is normalized before applying to radio."""
+        from app.models import AppSettings
+        from app.radio import RadioManager
+
+        rm = RadioManager()
+        mock_mc = MagicMock()
+        mock_mc.start_auto_message_fetching = AsyncMock()
+        mock_mc.commands.set_flood_scope = AsyncMock()
+        rm._meshcore = mock_mc
+
+        mock_settings = AppSettings(flood_scope="TestRegion")
+
+        with (
+            patch("app.event_handlers.register_event_handlers"),
+            patch("app.keystore.export_and_store_private_key", new_callable=AsyncMock),
+            patch("app.radio_sync.sync_radio_time", new_callable=AsyncMock),
+            patch(
+                "app.repository.AppSettingsRepository.get",
+                new_callable=AsyncMock,
+                return_value=mock_settings,
+            ),
+            patch("app.radio_sync.sync_and_offload_all", new_callable=AsyncMock, return_value={}),
+            patch("app.radio_sync.start_periodic_sync"),
+            patch("app.radio_sync.send_advertisement", new_callable=AsyncMock, return_value=False),
+            patch("app.radio_sync.start_periodic_advert"),
+            patch("app.radio_sync.drain_pending_messages", new_callable=AsyncMock, return_value=0),
+            patch("app.radio_sync.start_message_polling"),
+        ):
+            await rm.post_connect_setup()
+
+        mock_mc.commands.set_flood_scope.assert_awaited_once_with("#TestRegion")
+
     @pytest.mark.asyncio
     async def test_flood_scope_empty_resets_during_setup(self):
         """Empty flood_scope calls set_flood_scope("") during post_connect_setup."""
diff --git a/tests/test_send_messages.py b/tests/test_send_messages.py
index 43a6046..111bf25 100644
--- a/tests/test_send_messages.py
+++ b/tests/test_send_messages.py
@@ -279,8 +279,8 @@ class TestOutgoingChannelBroadcast:
         mc = _make_mc(name="MyNode")
         chan_key = "de" * 16
         await ChannelRepository.upsert(key=chan_key, name="#flightless")
-        await ChannelRepository.update_flood_scope_override(chan_key, "#Esperance")
-        await AppSettingsRepository.update(flood_scope="#Baseline")
+        await ChannelRepository.update_flood_scope_override(chan_key, "Esperance")
+        await AppSettingsRepository.update(flood_scope="Baseline")
 
         with (
             patch("app.routers.messages.require_connected", return_value=mc),
@@ -303,8 +303,8 @@ class TestOutgoingChannelBroadcast:
         mc = _make_mc(name="MyNode")
         chan_key = "df" * 16
         await ChannelRepository.upsert(key=chan_key, name="#matching")
-        await ChannelRepository.update_flood_scope_override(chan_key, "#Esperance")
-        await AppSettingsRepository.update(flood_scope="#Esperance")
+        await ChannelRepository.update_flood_scope_override(chan_key, "Esperance")
+        await AppSettingsRepository.update(flood_scope="Esperance")
 
         with (
             patch("app.routers.messages.require_connected", return_value=mc),
diff --git a/tests/test_settings_router.py b/tests/test_settings_router.py
index e2b39cf..28e2f0b 100644
--- a/tests/test_settings_router.py
+++ b/tests/test_settings_router.py
@@ -55,7 +55,7 @@ class TestUpdateSettings:
     @pytest.mark.asyncio
     async def test_flood_scope_round_trip(self, test_db):
         """Flood scope should be saved and retrieved correctly."""
-        result = await update_settings(AppSettingsUpdate(flood_scope="#MyRegion"))
+        result = await update_settings(AppSettingsUpdate(flood_scope="MyRegion"))
         assert result.flood_scope == "#MyRegion"
 
         fresh = await AppSettingsRepository.get()
@@ -70,7 +70,13 @@ class TestUpdateSettings:
     @pytest.mark.asyncio
     async def test_flood_scope_whitespace_stripped(self, test_db):
         """Flood scope should be stripped of whitespace."""
-        result = await update_settings(AppSettingsUpdate(flood_scope="  #MyRegion  "))
+        result = await update_settings(AppSettingsUpdate(flood_scope="  MyRegion  "))
+        assert result.flood_scope == "#MyRegion"
+
+    @pytest.mark.asyncio
+    async def test_flood_scope_existing_hash_is_not_doubled(self, test_db):
+        """Existing leading hash should be preserved for backward compatibility."""
+        result = await update_settings(AppSettingsUpdate(flood_scope="#MyRegion"))
         assert result.flood_scope == "#MyRegion"
 
     @pytest.mark.asyncio
@@ -92,7 +98,7 @@ class TestUpdateSettings:
         mock_rm.radio_operation = mock_radio_op
 
         with patch("app.radio.radio_manager", mock_rm):
-            await update_settings(AppSettingsUpdate(flood_scope="#TestRegion"))
+            await update_settings(AppSettingsUpdate(flood_scope="TestRegion"))
 
         mock_mc.commands.set_flood_scope.assert_awaited_once_with("#TestRegion")