diff --git a/example-config.yml b/example-config.yml
index 79a242954..d62b241ae 100644
--- a/example-config.yml
+++ b/example-config.yml
@@ -268,7 +268,11 @@ modes:
       iconName: wheelchair
       type: CHECKBOX # Possible options: CHECKBOX, SUBMODE, SLIDER, DROPDOWN
   transitModes:
-    - mode: BUS
+      # Mode can be a string or an array of strings.
+    - mode: ["TROLLEYBUS", "BUS"]
+      # When mode is an array an overrideMode must be provided.
+      # This specifies the displayed mode used for icon and URL param.
+      overrideMode: BUS
       label: Bus
       # A mode color can be added, used throughout the application,
       # most notably in the enhanced stop viewer bubble
diff --git a/lib/actions/form.js b/lib/actions/form.js
index bfdc65fe7..61ef9b87f 100644
--- a/lib/actions/form.js
+++ b/lib/actions/form.js
@@ -43,7 +43,7 @@ export function resetForm(full = false) {
       const options = getTripOptionsFromQuery(defaultQuery)
       // Default mode is currently WALK,TRANSIT. We need to update this value
       // here to match the list of modes, otherwise the form will break.
-      options.mode = ['WALK', ...transitModes.map((m) => m.mode)].join(',')
+      options.mode = ['WALK', ...transitModes.flatMap((m) => m.mode)].join(',')
       dispatch(settingQueryParam(options))
     }
     if (full) {
diff --git a/lib/reducers/create-otp-reducer.js b/lib/reducers/create-otp-reducer.js
index 0bc899936..b84951935 100644
--- a/lib/reducers/create-otp-reducer.js
+++ b/lib/reducers/create-otp-reducer.js
@@ -135,10 +135,18 @@ export function getInitialState(userDefinedConfig) {
 
   const transitModeSettings = config?.modes?.transitModes.map((transitMode) => {
     const { mode, overrideMode } = transitMode
+    if (Array.isArray(mode) && !overrideMode) {
+      console.warn(
+        `Mode ${mode} is an array, but no overrideMode is specified.`
+      )
+    }
     const displayedMode = overrideMode || mode
+    const addTransportModes = Array.isArray(mode)
+      ? mode.map((m) => ({ mode: m }))
+      : { mode }
     return {
       // This is the mode that gets added to the actual query to OTP
-      addTransportMode: { mode },
+      addTransportMode: addTransportModes,
       applicableMode: 'TRANSIT',
       default: true,
       iconName: displayedMode.toLowerCase(),
diff --git a/lib/util/config-types.ts b/lib/util/config-types.ts
index 80f9cf10f..e0abbaf11 100644
--- a/lib/util/config-types.ts
+++ b/lib/util/config-types.ts
@@ -312,7 +312,7 @@ export interface GeocoderConfig extends GeocoderConfigOtpUI {
 export interface TransitModeConfig {
   color?: string
   label?: string
-  mode: string
+  mode: string | string[]
   showWheelchairSetting?: boolean
 }