diff --git a/CHANGES.txt b/CHANGES.txt
index 601667457b..6efcaa3874 100644
--- a/CHANGES.txt
+++ b/CHANGES.txt
@@ -37,6 +37,7 @@
  * More fixes to the TokenAllocator (CASSANDRA-12990)
  * NoReplicationTokenAllocator should work with zero replication factor (CASSANDRA-12983)
 Merged from 3.0:
+ * Use keyspace replication settings on system.size_estimates table (CASSANDRA-9639)
  * Add vm.max_map_count StartupCheck (CASSANDRA-13008)
  * Obfuscate password in stress-graphs (CASSANDRA-12233)
  * Hint related logging should include the IP address of the destination in addition to
diff --git a/NEWS.txt b/NEWS.txt
index 9c183f601b..d936dbe73e 100644
--- a/NEWS.txt
+++ b/NEWS.txt
@@ -22,9 +22,6 @@ New features
      See CASSANDRA-11936
    - Support for arithmetic operations on number has been added. See CASSANDRA-11935
 
-3.11
-====
-
 Upgrading
 ---------
     - Cassandra 4.0 removed support for the deprecated Thrift interface. Amongst
@@ -47,6 +44,14 @@ Upgrading
       repaired. For incremental repairs, anticompaction is run at the beginning
       of the repair, instead of at the end.
 
+3.11.0
+======
+
+Upgrading
+---------
+   - Primary ranges in the system.size_estimates table are now based on the keyspace
+     replication settings and adjacent ranges are no longer merged (CASSANDRA-9639).
+
 3.10
 ====
 
diff --git a/src/java/org/apache/cassandra/db/SizeEstimatesRecorder.java b/src/java/org/apache/cassandra/db/SizeEstimatesRecorder.java
index f70e45e63a..066b2fe178 100644
--- a/src/java/org/apache/cassandra/db/SizeEstimatesRecorder.java
+++ b/src/java/org/apache/cassandra/db/SizeEstimatesRecorder.java
@@ -68,12 +68,10 @@ public class SizeEstimatesRecorder extends SchemaChangeListener implements Runna
 
         logger.trace("Recording size estimates");
 
-        // find primary token ranges for the local node.
-        Collection<Token> localTokens = StorageService.instance.getLocalTokens();
-        Collection<Range<Token>> localRanges = metadata.getPrimaryRangesFor(localTokens);
-
         for (Keyspace keyspace : Keyspace.nonLocalStrategy())
         {
+            Collection<Range<Token>> localRanges = StorageService.instance.getPrimaryRangesForEndpoint(keyspace.getName(),
+                    FBUtilities.getBroadcastAddress());
             for (ColumnFamilyStore table : keyspace.getColumnFamilyStores())
             {
                 long start = System.nanoTime();
@@ -90,37 +88,39 @@ public class SizeEstimatesRecorder extends SchemaChangeListener implements Runna
     @SuppressWarnings("resource")
     private void recordSizeEstimates(ColumnFamilyStore table, Collection<Range<Token>> localRanges)
     {
-        List<Range<Token>> unwrappedRanges = Range.normalize(localRanges);
         // for each local primary range, estimate (crudely) mean partition size and partitions count.
         Map<Range<Token>, Pair<Long, Long>> estimates = new HashMap<>(localRanges.size());
-        for (Range<Token> range : unwrappedRanges)
+        for (Range<Token> localRange : localRanges)
         {
-            // filter sstables that have partitions in this range.
-            Refs<SSTableReader> refs = null;
-            long partitionsCount, meanPartitionSize;
-
-            try
+            for (Range<Token> unwrappedRange : localRange.unwrap())
             {
-                while (refs == null)
+                // filter sstables that have partitions in this range.
+                Refs<SSTableReader> refs = null;
+                long partitionsCount, meanPartitionSize;
+
+                try
                 {
-                    Iterable<SSTableReader> sstables = table.getTracker().getView().select(SSTableSet.CANONICAL);
-                    SSTableIntervalTree tree = SSTableIntervalTree.build(sstables);
-                    Range<PartitionPosition> r = Range.makeRowRange(range);
-                    Iterable<SSTableReader> canonicalSSTables = View.sstablesInBounds(r.left, r.right, tree);
-                    refs = Refs.tryRef(canonicalSSTables);
+                    while (refs == null)
+                    {
+                        Iterable<SSTableReader> sstables = table.getTracker().getView().select(SSTableSet.CANONICAL);
+                        SSTableIntervalTree tree = SSTableIntervalTree.build(sstables);
+                        Range<PartitionPosition> r = Range.makeRowRange(unwrappedRange);
+                        Iterable<SSTableReader> canonicalSSTables = View.sstablesInBounds(r.left, r.right, tree);
+                        refs = Refs.tryRef(canonicalSSTables);
+                    }
+
+                    // calculate the estimates.
+                    partitionsCount = estimatePartitionsCount(refs, unwrappedRange);
+                    meanPartitionSize = estimateMeanPartitionSize(refs);
+                }
+                finally
+                {
+                    if (refs != null)
+                        refs.release();
                 }
 
-                // calculate the estimates.
-                partitionsCount = estimatePartitionsCount(refs, range);
-                meanPartitionSize = estimateMeanPartitionSize(refs);
+                estimates.put(unwrappedRange, Pair.create(partitionsCount, meanPartitionSize));
             }
-            finally
-            {
-                if (refs != null)
-                    refs.release();
-            }
-
-            estimates.put(range, Pair.create(partitionsCount, meanPartitionSize));
         }
 
         // atomically update the estimates.
diff --git a/src/java/org/apache/cassandra/service/ActiveRepairService.java b/src/java/org/apache/cassandra/service/ActiveRepairService.java
index 89e1954a4a..c4979070d7 100644
--- a/src/java/org/apache/cassandra/service/ActiveRepairService.java
+++ b/src/java/org/apache/cassandra/service/ActiveRepairService.java
@@ -266,7 +266,10 @@ public class ActiveRepairService implements IEndpointStateChangeSubscriber, IFai
             }
             else if (range.intersects(toRepair))
             {
-                throw new IllegalArgumentException("Requested range intersects a local range but is not fully contained in one; this would lead to imprecise repair");
+                throw new IllegalArgumentException(String.format("Requested range %s intersects a local range (%s) " +
+                                                                 "but is not fully contained in one; this would lead to " +
+                                                                 "imprecise repair. keyspace: %s", toRepair.toString(),
+                                                                 range.toString(), keyspaceName));
             }
         }
         if (rangeSuperSet == null || !replicaSets.containsKey(rangeSuperSet))