diff --git a/example-config.yml b/example-config.yml
index cc270ada0..2bae9c943 100644
--- a/example-config.yml
+++ b/example-config.yml
@@ -310,6 +310,9 @@ itinerary:
   # Whether the plan first/previous/next/last buttons should be shown along with
   # plan trip itineraries.
   showPlanFirstLastButtons: false
+  # Filters out trips returned by OTP by default, unless specifically requested.
+  # e.g. filters out walk-only itineraries if user has not explicitly asked for them.
+  strictItineraryFiltering: false
   # Whether to render route names and colors in the blocks inside
   # the batch ui rows
   renderRouteNamesInBlocks: true
diff --git a/lib/actions/apiV2.js b/lib/actions/apiV2.js
index 3290f9afd..55bacbcc8 100644
--- a/lib/actions/apiV2.js
+++ b/lib/actions/apiV2.js
@@ -46,7 +46,8 @@ import { RoutingQueryCallResult } from './api-constants'
 import { setItineraryView } from './ui'
 import { zoomToPlace } from './map'
 
-const { generateCombinations, generateOtp2Query } = coreUtils.queryGen
+const { generateCombinations, generateOtp2Query, SIMPLIFICATIONS } =
+  coreUtils.queryGen
 const { getTripOptionsFromQuery, getUrlParams } = coreUtils.query
 const { convertGraphQLResponseToLegacy } = coreUtils.itinerary
 const { randId } = coreUtils.storage
@@ -825,6 +826,8 @@ export function routingQuery(searchId = null, updateSearchInReducer) {
       config?.modes?.initialState?.enabledModeButtons ||
       {}
 
+    const strictModes = config?.itinerary?.strictItineraryFiltering
+
     // Filter mode definitions based on active mode keys
     const activeModeButtons = config.modes?.modeButtons.filter((mb) =>
       activeModeKeys.includes(mb.key)
@@ -919,11 +922,31 @@ export function routingQuery(searchId = null, updateSearchInReducer) {
           routingError,
           {
             rewritePayload: (response, dispatch, getState) => {
-              const withCollapsedShortNames =
-                response.data?.plan?.itineraries?.map((itin) => ({
+              const itineraries = response.data?.plan?.itineraries
+
+              // Convert user-selected transit modes from mode selector into modes recognized by OTP.
+              const activeModeStrings = activeModes.map(
+                (am) => SIMPLIFICATIONS[am.mode]
+              )
+
+              let filteredItineraries = itineraries
+              // If "strictItineraryFiltering" is enabled, only return itineraries that contain at least one explicitly requested mode...
+              if (strictModes) {
+                filteredItineraries = itineraries.filter((itin) =>
+                  itin.legs.some((leg) =>
+                    activeModeStrings.includes(SIMPLIFICATIONS[leg.mode])
+                  )
+                )
+                // ... Otherwise return all itineraries.
+              }
+
+              // Filter itineraries to collapse short names and hide unnecessary errors.
+              const withCollapsedShortNames = filteredItineraries.map(
+                (itin) => ({
                   ...itin,
                   legs: itin.legs?.map(convertGraphQLResponseToLegacy)
-                }))
+                })
+              )
 
               /* It is possible for a NO_TRANSIT_CONNECTION error to be
                 returned even if trips were returned, since it is on a mode-by-mode basis.