diff --git a/server/src/main/java/org/opensearch/action/search/AbstractSearchAsyncAction.java b/server/src/main/java/org/opensearch/action/search/AbstractSearchAsyncAction.java
index 0520a4a7aecec..c665cbdb30a59 100644
--- a/server/src/main/java/org/opensearch/action/search/AbstractSearchAsyncAction.java
+++ b/server/src/main/java/org/opensearch/action/search/AbstractSearchAsyncAction.java
@@ -425,8 +425,10 @@ public final void executeNextPhase(SearchPhase currentPhase, SearchPhase nextPha
                             currentPhase.getName()
                         );
                     }
-                    onPhaseFailure(currentPhase, "Partial shards failure (" + discrepancy + " shards unavailable)", null);
-                    return;
+                    if (!request.getIgnoreUnavailableShards()) {
+                        onPhaseFailure(currentPhase, "Partial shards failure (" + discrepancy + " shards unavailable)", null);
+                        return;
+                    }
                 }
             }
             if (logger.isTraceEnabled()) {
diff --git a/server/src/main/java/org/opensearch/action/search/SearchRequest.java b/server/src/main/java/org/opensearch/action/search/SearchRequest.java
index 3b8a6937815aa..c6fea74b2e041 100644
--- a/server/src/main/java/org/opensearch/action/search/SearchRequest.java
+++ b/server/src/main/java/org/opensearch/action/search/SearchRequest.java
@@ -102,6 +102,8 @@ public class SearchRequest extends ActionRequest implements IndicesRequest.Repla
 
     private Boolean allowPartialSearchResults;
 
+    private Boolean ignoreUnavailableShards;
+
     private Scroll scroll;
 
     private int batchedReduceSize = DEFAULT_BATCHED_REDUCE_SIZE;
@@ -198,6 +200,7 @@ private SearchRequest(
         boolean finalReduce
     ) {
         this.allowPartialSearchResults = searchRequest.allowPartialSearchResults;
+        this.ignoreUnavailableShards = searchRequest.ignoreUnavailableShards;
         this.batchedReduceSize = searchRequest.batchedReduceSize;
         this.ccsMinimizeRoundtrips = searchRequest.ccsMinimizeRoundtrips;
         this.indices = indices;
@@ -246,6 +249,9 @@ public SearchRequest(StreamInput in) throws IOException {
         maxConcurrentShardRequests = in.readVInt();
         preFilterShardSize = in.readOptionalVInt();
         allowPartialSearchResults = in.readOptionalBoolean();
+        if (in.getVersion().onOrAfter(Version.V_2_14_0)) {
+            ignoreUnavailableShards = in.readOptionalBoolean();
+        }
         localClusterAlias = in.readOptionalString();
         if (localClusterAlias != null) {
             absoluteStartMillis = in.readVLong();
@@ -283,6 +289,9 @@ public void writeTo(StreamOutput out) throws IOException {
         out.writeVInt(maxConcurrentShardRequests);
         out.writeOptionalVInt(preFilterShardSize);
         out.writeOptionalBoolean(allowPartialSearchResults);
+        if (out.getVersion().onOrAfter(Version.V_2_14_0)) {
+            out.writeOptionalBoolean(ignoreUnavailableShards);
+        }
         out.writeOptionalString(localClusterAlias);
         if (localClusterAlias != null) {
             out.writeVLong(absoluteStartMillis);
@@ -567,6 +576,15 @@ public Boolean allowPartialSearchResults() {
         return this.allowPartialSearchResults;
     }
 
+    public SearchRequest ignoreUnavailableShards(boolean ignoreUnavailableShards) {
+        this.ignoreUnavailableShards = ignoreUnavailableShards;
+        return this;
+    }
+
+    public Boolean getIgnoreUnavailableShards() {
+        return this.ignoreUnavailableShards;
+    }
+
     /**
      * Sets the number of shard results that should be reduced at once on the coordinating node. This value should be used as a protection
      * mechanism to reduce the memory overhead per search request if the potential number of shards in the request can be large.
@@ -747,6 +765,7 @@ public boolean equals(Object o) {
             && Objects.equals(preFilterShardSize, that.preFilterShardSize)
             && Objects.equals(indicesOptions, that.indicesOptions)
             && Objects.equals(allowPartialSearchResults, that.allowPartialSearchResults)
+            && Objects.equals(ignoreUnavailableShards, that.ignoreUnavailableShards)
             && Objects.equals(localClusterAlias, that.localClusterAlias)
             && absoluteStartMillis == that.absoluteStartMillis
             && ccsMinimizeRoundtrips == that.ccsMinimizeRoundtrips
@@ -770,6 +789,7 @@ public int hashCode() {
             maxConcurrentShardRequests,
             preFilterShardSize,
             allowPartialSearchResults,
+            ignoreUnavailableShards,
             localClusterAlias,
             absoluteStartMillis,
             ccsMinimizeRoundtrips,
@@ -805,6 +825,8 @@ public String toString() {
             + preFilterShardSize
             + ", allowPartialSearchResults="
             + allowPartialSearchResults
+            + ", ignoreUnavailableShards="
+            + ignoreUnavailableShards
             + ", localClusterAlias="
             + localClusterAlias
             + ", getOrCreateAbsoluteStartMillis="
diff --git a/server/src/main/java/org/opensearch/rest/action/search/RestSearchAction.java b/server/src/main/java/org/opensearch/rest/action/search/RestSearchAction.java
index 80dc34c4d5d68..2f2095c610da7 100644
--- a/server/src/main/java/org/opensearch/rest/action/search/RestSearchAction.java
+++ b/server/src/main/java/org/opensearch/rest/action/search/RestSearchAction.java
@@ -183,6 +183,11 @@ public static void parseSearchRequest(
             searchRequest.allowPartialSearchResults(request.paramAsBoolean("allow_partial_search_results", null));
         }
 
+        if (request.hasParam("ignore_unavailable_shards")) {
+            // only set if we have the parameter passed to override the cluster-level default
+            searchRequest.ignoreUnavailableShards(request.paramAsBoolean("ignore_unavailable_shards", null));
+        }
+
         if (request.hasParam("phase_took")) {
             // only set if we have the parameter passed to override the cluster-level default
             // else phaseTook = null