diff --git a/app/src/frontend/map/layers/city-base-map-layer.tsx b/app/src/frontend/map/layers/city-base-map-layer.tsx
index db6582a7..315b7573 100644
--- a/app/src/frontend/map/layers/city-base-map-layer.tsx
+++ b/app/src/frontend/map/layers/city-base-map-layer.tsx
@@ -3,7 +3,7 @@ import { TileLayer } from 'react-leaflet';
 
 import { MapTheme } from '../../config/map-config';
 
-const OS_API_KEY = 'NVUxtY5r8eA6eIfwrPTAGKrAAsoeI9E9';
+const OS_API_KEY = 'UVWEspgInusDKKYANE5bmyddoEmCSD4r';
 
 /**
  * Base raster layer for the map.
@@ -15,10 +15,10 @@ export function CityBaseMapLayer({theme}: {theme: MapTheme}) {
      * Ordnance Survey maps - UK / London specific
      * (replace with appropriate base map for other cities/countries)
      */
-    const key = OS_API_KEY;
-    const tilematrixSet = 'EPSG:3857';
-    const layer = theme === 'light' ? 'Light 3857' : 'Night 3857';
-    const baseUrl = `https://api2.ordnancesurvey.co.uk/mapping_api/v1/service/zxy/${tilematrixSet}/${layer}/{z}/{x}/{y}.png?key=${key}`;
+    const apiKey = OS_API_KEY;
+    const layer = theme === 'light' ? 'Light_3857' : 'Night 3857';
+    
+    const baseUrl = `https://api.os.uk/maps/raster/v1/zxy/${layer}/{z}/{x}/{y}.png?key=${apiKey}`;
     const attribution = 'Building attribute data is © Colouring London contributors. Maps contain OS data © Crown copyright: OS Maps baselayers and building outlines. <a href=/ordnance-survey-licence.html>OS licence</a>';
     
     return <TileLayer
diff --git a/app/src/frontend/map/map.tsx b/app/src/frontend/map/map.tsx
index 4216cf35..82af9e33 100644
--- a/app/src/frontend/map/map.tsx
+++ b/app/src/frontend/map/map.tsx
@@ -44,7 +44,7 @@ class ColouringMap extends Component<ColouringMapProps, ColouringMapState> {
     constructor(props) {
         super(props);
         this.state = {
-            theme: 'night',
+            theme: 'light',
             ...defaultMapPosition
         };
         this.handleClick = this.handleClick.bind(this);
@@ -104,7 +104,7 @@ class ColouringMap extends Component<ColouringMapProps, ColouringMapState> {
                         name={'cc-base-pane'}
                         style={{zIndex: 50}}
                     >
-                        {/* <CityBaseMapLayer theme={this.state.theme} /> */} {/* temporarily disable the base map due to OS account issues */}
+                        <CityBaseMapLayer theme={this.state.theme} />
                         <BuildingBaseLayer theme={this.state.theme} />
                     </Pane>
 
@@ -144,7 +144,7 @@ class ColouringMap extends Component<ColouringMapProps, ColouringMapState> {
                             </div>
                         }
                         <Legend legendConfig={categoryMapDefinition?.legend} />
-                        <ThemeSwitcher onSubmit={this.themeSwitch} currentTheme={this.state.theme} />
+                        {/* <ThemeSwitcher onSubmit={this.themeSwitch} currentTheme={this.state.theme} /> */}
                         <SearchBox onLocate={this.handleLocate} />
                     </Fragment>
                 }