diff --git a/core/src/main/java/org/elasticsearch/cluster/routing/allocation/decider/ShardsLimitAllocationDecider.java b/core/src/main/java/org/elasticsearch/cluster/routing/allocation/decider/ShardsLimitAllocationDecider.java
index 15f2cf20c1a..e6f0fbcd645 100644
--- a/core/src/main/java/org/elasticsearch/cluster/routing/allocation/decider/ShardsLimitAllocationDecider.java
+++ b/core/src/main/java/org/elasticsearch/cluster/routing/allocation/decider/ShardsLimitAllocationDecider.java
@@ -29,6 +29,8 @@ import org.elasticsearch.common.settings.Setting;
 import org.elasticsearch.common.settings.Setting.Property;
 import org.elasticsearch.common.settings.Settings;
 
+import java.util.function.BiPredicate;
+
 /**
  * This {@link AllocationDecider} limits the number of shards per node on a per
  * index or node-wide basis. The allocator prevents a single node to hold more
@@ -83,46 +85,17 @@ public class ShardsLimitAllocationDecider extends AllocationDecider {
 
     @Override
     public Decision canAllocate(ShardRouting shardRouting, RoutingNode node, RoutingAllocation allocation) {
-        IndexMetaData indexMd = allocation.metaData().getIndexSafe(shardRouting.index());
-        final int indexShardLimit = INDEX_TOTAL_SHARDS_PER_NODE_SETTING.get(indexMd.getSettings(), settings);
-        // Capture the limit here in case it changes during this method's
-        // execution
-        final int clusterShardLimit = this.clusterShardLimit;
-
-        if (indexShardLimit <= 0 && clusterShardLimit <= 0) {
-            return allocation.decision(Decision.YES, NAME, "total shard limits are disabled: [index: %d, cluster: %d] <= 0",
-                    indexShardLimit, clusterShardLimit);
-        }
-
-        int indexShardCount = 0;
-        int nodeShardCount = 0;
-        for (ShardRouting nodeShard : node) {
-            // don't count relocating shards...
-            if (nodeShard.relocating()) {
-                continue;
-            }
-            nodeShardCount++;
-            if (nodeShard.index().equals(shardRouting.index())) {
-                indexShardCount++;
-            }
-        }
-        if (clusterShardLimit > 0 && nodeShardCount >= clusterShardLimit) {
-            return allocation.decision(Decision.NO, NAME,
-                "too many shards [%d] allocated to this node, [%s=%d]",
-                nodeShardCount, CLUSTER_TOTAL_SHARDS_PER_NODE_SETTING.getKey(), clusterShardLimit);
-        }
-        if (indexShardLimit > 0 && indexShardCount >= indexShardLimit) {
-            return allocation.decision(Decision.NO, NAME,
-                "too many shards [%d] allocated to this node for index [%s], [%s=%d]",
-                indexShardCount, shardRouting.getIndexName(), INDEX_TOTAL_SHARDS_PER_NODE_SETTING.getKey(), indexShardLimit);
-        }
-        return allocation.decision(Decision.YES, NAME,
-                "the shard count [%d] for this node is under the index limit [%d] and cluster level node limit [%d]",
-                nodeShardCount, indexShardLimit, clusterShardLimit);
+        return doDecide(shardRouting, node, allocation, (count, limit) -> count >= limit);
     }
 
     @Override
     public Decision canRemain(ShardRouting shardRouting, RoutingNode node, RoutingAllocation allocation) {
+        return doDecide(shardRouting, node, allocation, (count, limit) -> count > limit);
+
+    }
+
+    private Decision doDecide(ShardRouting shardRouting, RoutingNode node, RoutingAllocation allocation,
+                              BiPredicate<Integer, Integer> decider) {
         IndexMetaData indexMd = allocation.metaData().getIndexSafe(shardRouting.index());
         final int indexShardLimit = INDEX_TOTAL_SHARDS_PER_NODE_SETTING.get(indexMd.getSettings(), settings);
         // Capture the limit here in case it changes during this method's
@@ -146,14 +119,13 @@ public class ShardsLimitAllocationDecider extends AllocationDecider {
                 indexShardCount++;
             }
         }
-        // Subtle difference between the `canAllocate` and `canRemain` is that
-        // this checks > while canAllocate checks >=
-        if (clusterShardLimit > 0 && nodeShardCount > clusterShardLimit) {
+
+        if (clusterShardLimit > 0 && decider.test(nodeShardCount, clusterShardLimit)) {
             return allocation.decision(Decision.NO, NAME,
                 "too many shards [%d] allocated to this node, [%s=%d]",
                 nodeShardCount, CLUSTER_TOTAL_SHARDS_PER_NODE_SETTING.getKey(), clusterShardLimit);
         }
-        if (indexShardLimit > 0 && indexShardCount > indexShardLimit) {
+        if (indexShardLimit > 0 && decider.test(indexShardCount, indexShardLimit)) {
             return allocation.decision(Decision.NO, NAME,
                 "too many shards [%d] allocated to this node for index [%s], [%s=%d]",
                 indexShardCount, shardRouting.getIndexName(), INDEX_TOTAL_SHARDS_PER_NODE_SETTING.getKey(), indexShardLimit);