diff --git a/core/src/main/java/org/elasticsearch/cluster/routing/RoutingService.java b/core/src/main/java/org/elasticsearch/cluster/routing/RoutingService.java
index ed7c5c46aa3..db0a46de633 100644
--- a/core/src/main/java/org/elasticsearch/cluster/routing/RoutingService.java
+++ b/core/src/main/java/org/elasticsearch/cluster/routing/RoutingService.java
@@ -118,11 +118,17 @@ public class RoutingService extends AbstractLifecycleComponent<RoutingService> i
             if (nextDelaySetting > 0 && nextDelaySetting < registeredNextDelaySetting) {
                 FutureUtils.cancel(registeredNextDelayFuture);
                 registeredNextDelaySetting = nextDelaySetting;
-                // We use System.currentTimeMillis here because we want the
-                // next delay from the "now" perspective, rather than the
-                // delay from the last time the GatewayAllocator tried to
-                // assign/delay the shard
-                TimeValue nextDelay = TimeValue.timeValueMillis(UnassignedInfo.findNextDelayedAllocationIn(System.currentTimeMillis(), settings, event.state()));
+                // We calculate nextDelay based on System.currentTimeMillis() here because we want the next delay from the "now" perspective
+                // rather than the delay from the last time the GatewayAllocator tried to assign/delay the shard.
+                // The actual calculation is based on the latter though, to account for shards that should have been allocated
+                // between unassignedShardsAllocatedTimestamp and System.currentTimeMillis()
+                long nextDelayBasedOnUnassignedShardsAllocatedTimestamp = UnassignedInfo.findNextDelayedAllocationIn(unassignedShardsAllocatedTimestamp, settings, event.state());
+                // adjust from unassignedShardsAllocatedTimestamp to now
+                long nextDelayMillis = nextDelayBasedOnUnassignedShardsAllocatedTimestamp - (System.currentTimeMillis() - unassignedShardsAllocatedTimestamp);
+                if (nextDelayMillis < 0) {
+                    nextDelayMillis = 0;
+                }
+                TimeValue nextDelay = TimeValue.timeValueMillis(nextDelayMillis);
                 int unassignedDelayedShards = UnassignedInfo.getNumberOfDelayedUnassigned(unassignedShardsAllocatedTimestamp, settings, event.state());
                 if (unassignedDelayedShards > 0) {
                     logger.info("delaying allocation for [{}] unassigned shards, next check in [{}]",