diff --git a/lucene/CHANGES.txt b/lucene/CHANGES.txt
index 6bf393ebe25..34eeab33390 100644
--- a/lucene/CHANGES.txt
+++ b/lucene/CHANGES.txt
@@ -147,9 +147,12 @@ New Features
   filtering.  Range trees can also handle values larger than 64 bits.
   (Adrien Grand, Mike McCandless)
 
-* LUCENE-6647: Add GeoHash string utility APIs (Nick Knize, Mike
+* LUCENE-6647: Add GeoHash string utility APIs (Nick Knize via Mike
   McCandless).
 
+* LUCENE-6710: GeoPointField now uses full 64 bits (up from 62) to encode
+  lat/lon (Nick Knize via Mike McCandless).
+
 API Changes
 
 * LUCENE-6508: Simplify Lock api, there is now just 
diff --git a/lucene/sandbox/src/java/org/apache/lucene/search/GeoPointTermsEnum.java b/lucene/sandbox/src/java/org/apache/lucene/search/GeoPointTermsEnum.java
index c47f03f092b..37d30ec78f9 100644
--- a/lucene/sandbox/src/java/org/apache/lucene/search/GeoPointTermsEnum.java
+++ b/lucene/sandbox/src/java/org/apache/lucene/search/GeoPointTermsEnum.java
@@ -17,6 +17,7 @@ package org.apache.lucene.search;
  * limitations under the License.
  */
 
+import java.math.BigInteger;
 import java.util.Collections;
 import java.util.LinkedList;
 import java.util.List;
@@ -67,7 +68,13 @@ class GeoPointTermsEnum extends FilteredTermsEnum {
    */
   private final void computeRange(long term, final short shift) {
     final long split = term | (0x1L<<shift);
-    final long upperMax = term | ((0x1L<<(shift+1))-1);
+    assert shift < 64;
+    final long upperMax;
+    if (shift < 63) {
+      upperMax = term | ((1L << (shift+1))-1);
+    } else {
+      upperMax = 0xffffffffffffffffL;
+    }
     final long lowerMax = split-1;
 
     relateAndRecurse(term, lowerMax, shift);
@@ -88,7 +95,7 @@ class GeoPointTermsEnum extends FilteredTermsEnum {
     final double maxLon = GeoUtils.mortonUnhashLon(end);
     final double maxLat = GeoUtils.mortonUnhashLat(end);
 
-    final short level = (short)(62-res>>>1);
+    final short level = (short)((GeoUtils.BITS<<1)-res>>>1);
 
     // if cell is within and a factor of the precision step, or it crosses the edge of the shape add the range
     final boolean within = res % GeoPointField.PRECISION_STEP == 0 && cellWithin(minLon, minLat, maxLon, maxLat);
diff --git a/lucene/sandbox/src/java/org/apache/lucene/util/GeoUtils.java b/lucene/sandbox/src/java/org/apache/lucene/util/GeoUtils.java
index 05f861dbd86..48cd1ad5eb4 100644
--- a/lucene/sandbox/src/java/org/apache/lucene/util/GeoUtils.java
+++ b/lucene/sandbox/src/java/org/apache/lucene/util/GeoUtils.java
@@ -27,9 +27,9 @@ import java.util.ArrayList;
 public final class GeoUtils {
   private static final short MIN_LON = -180;
   private static final short MIN_LAT = -90;
-  public static final short BITS = 31;
-  private static final double LON_SCALE = (0x1L<<BITS)/360.0D;
-  private static final double LAT_SCALE = (0x1L<<BITS)/180.0D;
+  public static final short BITS = 32;
+  private static final double LON_SCALE = ((0x1L<<BITS)-1)/360.0D;
+  private static final double LAT_SCALE = ((0x1L<<BITS)-1)/180.0D;
   public static final double TOLERANCE = 1E-6;
 
   /** Minimum longitude value. */
diff --git a/lucene/sandbox/src/test/org/apache/lucene/search/TestGeoPointQuery.java b/lucene/sandbox/src/test/org/apache/lucene/search/TestGeoPointQuery.java
index ace8c7fb5a2..5b1e9dd1fd0 100644
--- a/lucene/sandbox/src/test/org/apache/lucene/search/TestGeoPointQuery.java
+++ b/lucene/sandbox/src/test/org/apache/lucene/search/TestGeoPointQuery.java
@@ -239,6 +239,13 @@ public class TestGeoPointQuery extends LuceneTestCase {
     doTestRandom(10000);
   }
 
+  @Test
+  public void testMortonEncoding() throws Exception {
+    long hash = GeoUtils.mortonHash(180, 90);
+    assertEquals(180.0, GeoUtils.mortonUnhashLon(hash), 0);
+    assertEquals(90.0, GeoUtils.mortonUnhashLat(hash), 0);
+  }
+
   @Nightly
   public void testRandomBig() throws Exception {
     doTestRandom(200000);