diff --git a/solr/core/src/java/org/apache/solr/search/facet/FacetProcessor.java b/solr/core/src/java/org/apache/solr/search/facet/FacetProcessor.java
index d5a4e23bb08..27cdaec1ec2 100644
--- a/solr/core/src/java/org/apache/solr/search/facet/FacetProcessor.java
+++ b/solr/core/src/java/org/apache/solr/search/facet/FacetProcessor.java
@@ -312,7 +312,7 @@ public abstract class FacetProcessor<FacetRequestT extends FacetRequest>  {
   }
 
   // note: only called by enum/stream prior to collect
-  void resetStats() {
+  void resetStats() throws IOException {
     countAcc.reset();
     for (SlotAcc acc : accs) {
       acc.reset();
diff --git a/solr/core/src/java/org/apache/solr/search/facet/HLLAgg.java b/solr/core/src/java/org/apache/solr/search/facet/HLLAgg.java
index 28c95e86e96..80e2bc1fb1a 100644
--- a/solr/core/src/java/org/apache/solr/search/facet/HLLAgg.java
+++ b/solr/core/src/java/org/apache/solr/search/facet/HLLAgg.java
@@ -52,16 +52,16 @@ public class HLLAgg extends StrAggValueSource {
     SchemaField sf = fcontext.qcontext.searcher().getSchema().getField(getArg());
     if (sf.multiValued() || sf.getType().multiValuedFieldCache()) {
       if (sf.hasDocValues()) {
-        return new UniqueMultiDvSlotAcc(fcontext, getArg(), numSlots, fcontext.isShard() ? factory : null);
+        return new UniqueMultiDvSlotAcc(fcontext, sf, numSlots, fcontext.isShard() ? factory : null);
       } else {
-        return new UniqueMultivaluedSlotAcc(fcontext, getArg(), numSlots, fcontext.isShard() ? factory : null);
+        return new UniqueMultivaluedSlotAcc(fcontext, sf, numSlots, fcontext.isShard() ? factory : null);
       }
     } else {
       if (sf.getType().getNumberType() != null) {
         // always use hll here since we don't know how many values there are?
         return new NumericAcc(fcontext, getArg(), numSlots);
       } else {
-        return new UniqueSinglevaluedSlotAcc(fcontext, getArg(), numSlots, fcontext.isShard() ? factory : null);
+        return new UniqueSinglevaluedSlotAcc(fcontext, sf, numSlots, fcontext.isShard() ? factory : null);
       }
     }
   }
diff --git a/solr/core/src/java/org/apache/solr/search/facet/SlotAcc.java b/solr/core/src/java/org/apache/solr/search/facet/SlotAcc.java
index 1d8aecb2e5f..f5cdf82f445 100644
--- a/solr/core/src/java/org/apache/solr/search/facet/SlotAcc.java
+++ b/solr/core/src/java/org/apache/solr/search/facet/SlotAcc.java
@@ -94,7 +94,7 @@ public abstract class SlotAcc implements Closeable {
     }
   }
 
-  public abstract void reset();
+  public abstract void reset() throws IOException;
 
   public abstract void resize(Resizer resizer);
 
diff --git a/solr/core/src/java/org/apache/solr/search/facet/UniqueAgg.java b/solr/core/src/java/org/apache/solr/search/facet/UniqueAgg.java
index 4cdfe02b5a5..4775e5fc8fe 100644
--- a/solr/core/src/java/org/apache/solr/search/facet/UniqueAgg.java
+++ b/solr/core/src/java/org/apache/solr/search/facet/UniqueAgg.java
@@ -43,15 +43,15 @@ public class UniqueAgg extends StrAggValueSource {
     SchemaField sf = fcontext.qcontext.searcher().getSchema().getField(getArg());
     if (sf.multiValued() || sf.getType().multiValuedFieldCache()) {
       if (sf.hasDocValues()) {
-        return new UniqueMultiDvSlotAcc(fcontext, getArg(), numSlots, null);
+        return new UniqueMultiDvSlotAcc(fcontext, sf, numSlots, null);
       } else {
-        return new UniqueMultivaluedSlotAcc(fcontext, getArg(), numSlots, null);
+        return new UniqueMultivaluedSlotAcc(fcontext, sf, numSlots, null);
       }
     } else {
       if (sf.getType().getNumberType() != null) {
         return new NumericAcc(fcontext, getArg(), numSlots);
       } else {
-        return new UniqueSinglevaluedSlotAcc(fcontext, getArg(), numSlots, null);
+        return new UniqueSinglevaluedSlotAcc(fcontext, sf, numSlots, null);
       }
     }
   }
diff --git a/solr/core/src/java/org/apache/solr/search/facet/UniqueMultiDvSlotAcc.java b/solr/core/src/java/org/apache/solr/search/facet/UniqueMultiDvSlotAcc.java
index 72a88ca4c64..65fa81ac6ab 100644
--- a/solr/core/src/java/org/apache/solr/search/facet/UniqueMultiDvSlotAcc.java
+++ b/solr/core/src/java/org/apache/solr/search/facet/UniqueMultiDvSlotAcc.java
@@ -25,19 +25,23 @@ import org.apache.lucene.index.SortedSetDocValues;
 import org.apache.lucene.util.BytesRef;
 import org.apache.lucene.util.FixedBitSet;
 import org.apache.lucene.util.LongValues;
-import org.apache.solr.search.SolrIndexSearcher;
+import org.apache.solr.schema.SchemaField;
 
 class UniqueMultiDvSlotAcc extends UniqueSlotAcc {
-  final SortedSetDocValues topLevel;
-  final SortedSetDocValues[] subDvs;
-  final MultiDocValues.OrdinalMap ordMap;
+  SortedSetDocValues topLevel;
+  SortedSetDocValues[] subDvs;
+  MultiDocValues.OrdinalMap ordMap;
   LongValues toGlobal;
   SortedSetDocValues subDv;
 
-  public UniqueMultiDvSlotAcc(FacetContext fcontext, String field, int numSlots, HLLAgg.HLLFactory factory) throws IOException {
+  public UniqueMultiDvSlotAcc(FacetContext fcontext, SchemaField field, int numSlots, HLLAgg.HLLFactory factory) throws IOException {
     super(fcontext, field, numSlots, factory);
-    SolrIndexSearcher searcher = fcontext.qcontext.searcher();
-    topLevel = FieldUtil.getSortedSetDocValues(fcontext.qcontext, searcher.getSchema().getField(field), null);
+  }
+
+  @Override
+  public void reset() throws IOException {
+    super.reset();
+    topLevel = FieldUtil.getSortedSetDocValues(fcontext.qcontext, field, null);
     nTerms = (int) topLevel.getValueCount();
     if (topLevel instanceof MultiDocValues.MultiSortedSetDocValues) {
       ordMap = ((MultiDocValues.MultiSortedSetDocValues) topLevel).mapping;
@@ -55,6 +59,9 @@ class UniqueMultiDvSlotAcc extends UniqueSlotAcc {
 
   @Override
   public void setNextReader(LeafReaderContext readerContext) throws IOException {
+    if (topLevel == null) {
+      reset();
+    }
     super.setNextReader(readerContext);
     if (subDvs != null) {
       subDv = subDvs[readerContext.ord];
diff --git a/solr/core/src/java/org/apache/solr/search/facet/UniqueMultivaluedSlotAcc.java b/solr/core/src/java/org/apache/solr/search/facet/UniqueMultivaluedSlotAcc.java
index 56a498e4389..10adcf06dd2 100644
--- a/solr/core/src/java/org/apache/solr/search/facet/UniqueMultivaluedSlotAcc.java
+++ b/solr/core/src/java/org/apache/solr/search/facet/UniqueMultivaluedSlotAcc.java
@@ -21,16 +21,17 @@ import java.io.IOException;
 
 import org.apache.lucene.util.BytesRef;
 import org.apache.lucene.util.FixedBitSet;
+import org.apache.solr.schema.SchemaField;
 import org.apache.solr.search.SolrIndexSearcher;
 
 class UniqueMultivaluedSlotAcc extends UniqueSlotAcc implements UnInvertedField.Callback {
   private UnInvertedField uif;
   private UnInvertedField.DocToTerm docToTerm;
 
-  public UniqueMultivaluedSlotAcc(FacetContext fcontext, String field, int numSlots, HLLAgg.HLLFactory factory) throws IOException {
+  public UniqueMultivaluedSlotAcc(FacetContext fcontext, SchemaField field, int numSlots, HLLAgg.HLLFactory factory) throws IOException {
     super(fcontext, field, numSlots, factory);
     SolrIndexSearcher searcher = fcontext.qcontext.searcher();
-    uif = UnInvertedField.getUnInvertedField(field, searcher);
+    uif = UnInvertedField.getUnInvertedField(field.getName(), searcher);
     docToTerm = uif.new DocToTerm();
     fcontext.qcontext.addCloseHook(this);  // TODO: find way to close accumulators instead of using close hook?
     nTerms = uif.numTerms();
diff --git a/solr/core/src/java/org/apache/solr/search/facet/UniqueSinglevaluedSlotAcc.java b/solr/core/src/java/org/apache/solr/search/facet/UniqueSinglevaluedSlotAcc.java
index e0a1852399f..b39f2823453 100644
--- a/solr/core/src/java/org/apache/solr/search/facet/UniqueSinglevaluedSlotAcc.java
+++ b/solr/core/src/java/org/apache/solr/search/facet/UniqueSinglevaluedSlotAcc.java
@@ -25,19 +25,26 @@ import org.apache.lucene.index.SortedDocValues;
 import org.apache.lucene.util.BytesRef;
 import org.apache.lucene.util.FixedBitSet;
 import org.apache.lucene.util.LongValues;
+import org.apache.solr.schema.SchemaField;
 import org.apache.solr.search.SolrIndexSearcher;
 
 class UniqueSinglevaluedSlotAcc extends UniqueSlotAcc {
-  final SortedDocValues topLevel;
-  final SortedDocValues[] subDvs;
-  final MultiDocValues.OrdinalMap ordMap;
+  SortedDocValues topLevel;
+  SortedDocValues[] subDvs;
+  MultiDocValues.OrdinalMap ordMap;
   LongValues toGlobal;
   SortedDocValues subDv;
 
-  public UniqueSinglevaluedSlotAcc(FacetContext fcontext, String field, int numSlots, HLLAgg.HLLFactory factory) throws IOException {
+  public UniqueSinglevaluedSlotAcc(FacetContext fcontext, SchemaField field, int numSlots, HLLAgg.HLLFactory factory) throws IOException {
     super(fcontext, field, numSlots, factory);
+    // let setNextReader lazily call reset(), that way an extra call to reset() after creation won't matter
+  }
+
+  @Override
+  public void reset() throws IOException {
+    super.reset();
     SolrIndexSearcher searcher = fcontext.qcontext.searcher();
-    topLevel = FieldUtil.getSortedDocValues(fcontext.qcontext, searcher.getSchema().getField(field), null);
+    topLevel = FieldUtil.getSortedDocValues(fcontext.qcontext, field, null);
     nTerms = topLevel.getValueCount();
     if (topLevel instanceof MultiDocValues.MultiSortedDocValues) {
       ordMap = ((MultiDocValues.MultiSortedDocValues)topLevel).mapping;
@@ -55,6 +62,9 @@ class UniqueSinglevaluedSlotAcc extends UniqueSlotAcc {
 
   @Override
   public void setNextReader(LeafReaderContext readerContext) throws IOException {
+    if (topLevel == null) {
+      reset();
+    }
     super.setNextReader(readerContext);
     if (subDvs != null) {
       subDv = subDvs[readerContext.ord];
diff --git a/solr/core/src/java/org/apache/solr/search/facet/UniqueSlotAcc.java b/solr/core/src/java/org/apache/solr/search/facet/UniqueSlotAcc.java
index ae542ac5e7f..607b0674b79 100644
--- a/solr/core/src/java/org/apache/solr/search/facet/UniqueSlotAcc.java
+++ b/solr/core/src/java/org/apache/solr/search/facet/UniqueSlotAcc.java
@@ -37,15 +37,15 @@ abstract class UniqueSlotAcc extends SlotAcc {
   int[] counts;  // populated with the cardinality once
   int nTerms;
 
-  public UniqueSlotAcc(FacetContext fcontext, String field, int numSlots, HLLAgg.HLLFactory factory) throws IOException {
+  public UniqueSlotAcc(FacetContext fcontext, SchemaField field, int numSlots, HLLAgg.HLLFactory factory) throws IOException {
     super(fcontext);
     this.factory = factory;
     arr = new FixedBitSet[numSlots];
-    this.field = fcontext.searcher.getSchema().getField(field);
+    this.field = field;
   }
 
   @Override
-  public void reset() {
+  public void reset() throws IOException {
     counts = null;
     for (FixedBitSet bits : arr) {
       if (bits == null) continue;
diff --git a/solr/core/src/test/org/apache/solr/search/facet/TestJsonFacets.java b/solr/core/src/test/org/apache/solr/search/facet/TestJsonFacets.java
index 3f31cca5bc3..4fcee671e14 100644
--- a/solr/core/src/test/org/apache/solr/search/facet/TestJsonFacets.java
+++ b/solr/core/src/test/org/apache/solr/search/facet/TestJsonFacets.java
@@ -1360,6 +1360,15 @@ public class TestJsonFacets extends SolrTestCaseHS {
             "}"
     );
 
+    // test acc reuse (i.e. reset() method).  This is normally used for stats that are not calculated in the first phase,
+    // currently non-sorting stats.
+    client.testJQ(params(p, "q", "*:*"
+        , "json.facet", "{f1:{type:terms, field:'${cat_s}', facet:{h:'hll(${where_s})'}   }}"
+        )
+        , "facets=={ 'count':6, " +
+            "'f1':{  buckets:[{val:B, count:3, h:2},{val:A, count:2, h:2}] } } "
+    );
+
   }
 
   @Test