diff --git a/src/lib/moment/prototype.js b/src/lib/moment/prototype.js
index bbea60146d..d472b1571d 100644
--- a/src/lib/moment/prototype.js
+++ b/src/lib/moment/prototype.js
@@ -87,6 +87,7 @@ import {
     getSetISOWeekYear,
     getWeeksInYear,
     getISOWeeksInYear,
+    getWeeksInWeekYear,
 } from '../units/week-year';
 proto.weekYear = getSetWeekYear;
 proto.isoWeekYear = getSetISOWeekYear;
@@ -105,6 +106,7 @@ import { getSetWeek, getSetISOWeek } from '../units/week';
 proto.week = proto.weeks = getSetWeek;
 proto.isoWeek = proto.isoWeeks = getSetISOWeek;
 proto.weeksInYear = getWeeksInYear;
+proto.weeksInWeekYear = getWeeksInWeekYear;
 proto.isoWeeksInYear = getISOWeeksInYear;
 
 // Day
diff --git a/src/lib/units/week-year.js b/src/lib/units/week-year.js
index 7e9815e2cd..daf5af70dc 100644
--- a/src/lib/units/week-year.js
+++ b/src/lib/units/week-year.js
@@ -107,10 +107,15 @@ export function getISOWeeksInYear() {
 }
 
 export function getWeeksInYear() {
-    var weekInfo = this.localeData()._week;
+    let weekInfo = this.localeData()._week;
     return weeksInYear(this.year(), weekInfo.dow, weekInfo.doy);
 }
 
+export function getWeeksInWeekYear() {
+    let weekInfo = this.localeData()._week;
+    return weeksInYear(this.weekYear(), weekInfo.dow, weekInfo.doy);
+}
+
 function getSetWeekYearHelper(input, week, weekday, dow, doy) {
     var weeksTarget;
     if (input == null) {
diff --git a/src/test/moment/weeks_in_year.js b/src/test/moment/weeks_in_year.js
index 99472e9105..b8bef36125 100644
--- a/src/test/moment/weeks_in_year.js
+++ b/src/test/moment/weeks_in_year.js
@@ -94,52 +94,69 @@ test('isoWeeksInYear first day of ISO Year', function (assert) {
 test('weeksInYear doy/dow = 1/4', function (assert) {
     moment.locale('1/4', { week: { dow: 1, doy: 4 } });
 
-    assert.equal(moment([2004]).weeksInYear(), 53, '2004 has 53 weeks');
-    assert.equal(moment([2005]).weeksInYear(), 52, '2005 has 53 weeks');
-    assert.equal(moment([2006]).weeksInYear(), 52, '2006 has 53 weeks');
-    assert.equal(moment([2007]).weeksInYear(), 52, '2007 has 52 weeks');
-    assert.equal(moment([2008]).weeksInYear(), 52, '2008 has 53 weeks');
-    assert.equal(moment([2009]).weeksInYear(), 53, '2009 has 53 weeks');
-    assert.equal(moment([2010]).weeksInYear(), 52, '2010 has 52 weeks');
-    assert.equal(moment([2011]).weeksInYear(), 52, '2011 has 52 weeks');
-    assert.equal(moment([2012]).weeksInYear(), 52, '2012 has 52 weeks');
-    assert.equal(moment([2013]).weeksInYear(), 52, '2013 has 52 weeks');
-    assert.equal(moment([2014]).weeksInYear(), 52, '2014 has 52 weeks');
-    assert.equal(moment([2015]).weeksInYear(), 53, '2015 has 53 weeks');
+    assert.equal(moment('2004-01-01').weeksInYear(), 53, '2004 has 53 weeks');
+    assert.equal(moment('2005-01-01').weeksInYear(), 52, '2005 has 52 weeks');
+    assert.equal(
+        moment('2005-01-01').weeksInWeekYear(),
+        53,
+        '2005-01-01 is weekYear 2014, which has 53 weeks'
+    );
+    assert.equal(moment('2006-01-01').weeksInYear(), 52, '2006 has 52 weeks');
+    assert.equal(moment('2007-01-01').weeksInYear(), 52, '2007 has 52 weeks');
+    assert.equal(moment('2008-01-01').weeksInYear(), 52, '2008 has 52 weeks');
+    assert.equal(moment('2009-01-01').weeksInYear(), 53, '2009 has 53 weeks');
+    assert.equal(moment('2010-01-01').weeksInYear(), 52, '2010 has 52 weeks');
+    assert.equal(
+        moment('2010-01-01').weeksInWeekYear(),
+        53,
+        '2010-01-01 is weekYear 2009, which has 53 weeks'
+    );
+    assert.equal(moment('2011-01-01').weeksInYear(), 52, '2011 has 52 weeks');
+    assert.equal(moment('2012-01-01').weeksInYear(), 52, '2012 has 52 weeks');
+    assert.equal(moment('2013-01-01').weeksInYear(), 52, '2013 has 52 weeks');
+    assert.equal(moment('2014-01-01').weeksInYear(), 52, '2014 has 52 weeks');
+    assert.equal(moment('2015-01-01').weeksInYear(), 53, '2015 has 53 weeks');
+    assert.equal(moment('2016-01-01').weeksInYear(), 52, '2016 has 52 weeks');
+    assert.equal(
+        moment('2016-01-01').weeksInWeekYear(),
+        53,
+        '2016-01-01 is weekYear 2015, which has 53 weeks'
+    );
 });
 
 test('weeksInYear doy/dow = 6/12', function (assert) {
     moment.locale('6/12', { week: { dow: 6, doy: 12 } });
 
     assert.equal(moment([2004]).weeksInYear(), 53, '2004 has 53 weeks');
-    assert.equal(moment([2005]).weeksInYear(), 52, '2005 has 53 weeks');
-    assert.equal(moment([2006]).weeksInYear(), 52, '2006 has 53 weeks');
+    assert.equal(moment([2005]).weeksInYear(), 52, '2005 has 52 weeks');
+    assert.equal(moment([2006]).weeksInYear(), 52, '2006 has 52 weeks');
     assert.equal(moment([2007]).weeksInYear(), 52, '2007 has 52 weeks');
-    assert.equal(moment([2008]).weeksInYear(), 52, '2008 has 53 weeks');
-    assert.equal(moment([2009]).weeksInYear(), 52, '2009 has 53 weeks');
-    assert.equal(moment([2010]).weeksInYear(), 53, '2010 has 52 weeks');
+    assert.equal(moment([2008]).weeksInYear(), 52, '2008 has 52 weeks');
+    assert.equal(moment([2009]).weeksInYear(), 52, '2009 has 52 weeks');
+    assert.equal(moment([2010]).weeksInYear(), 53, '2010 has 53 weeks');
     assert.equal(moment([2011]).weeksInYear(), 52, '2011 has 52 weeks');
     assert.equal(moment([2012]).weeksInYear(), 52, '2012 has 52 weeks');
     assert.equal(moment([2013]).weeksInYear(), 52, '2013 has 52 weeks');
     assert.equal(moment([2014]).weeksInYear(), 52, '2014 has 52 weeks');
-    assert.equal(moment([2015]).weeksInYear(), 52, '2015 has 53 weeks');
+    assert.equal(moment([2015]).weeksInYear(), 52, '2015 has 52 weeks');
 });
 
 test('weeksInYear doy/dow = 1/7', function (assert) {
     moment.locale('1/7', { week: { dow: 1, doy: 7 } });
 
-    assert.equal(moment([2004]).weeksInYear(), 52, '2004 has 53 weeks');
-    assert.equal(moment([2005]).weeksInYear(), 52, '2005 has 53 weeks');
+    assert.equal(moment([2004]).weeksInYear(), 52, '2004 has 52 weeks');
+    assert.equal(moment([2005]).weeksInYear(), 52, '2005 has 52 weeks');
     assert.equal(moment([2006]).weeksInYear(), 53, '2006 has 53 weeks');
     assert.equal(moment([2007]).weeksInYear(), 52, '2007 has 52 weeks');
-    assert.equal(moment([2008]).weeksInYear(), 52, '2008 has 53 weeks');
-    assert.equal(moment([2009]).weeksInYear(), 52, '2009 has 53 weeks');
+    assert.equal(moment([2008]).weeksInYear(), 52, '2008 has 52 weeks');
+    assert.equal(moment([2009]).weeksInYear(), 52, '2009 has 52 weeks');
     assert.equal(moment([2010]).weeksInYear(), 52, '2010 has 52 weeks');
     assert.equal(moment([2011]).weeksInYear(), 52, '2011 has 52 weeks');
-    assert.equal(moment([2012]).weeksInYear(), 53, '2012 has 52 weeks');
+    assert.equal(moment([2012]).weeksInYear(), 53, '2012 has 53 weeks');
     assert.equal(moment([2013]).weeksInYear(), 52, '2013 has 52 weeks');
     assert.equal(moment([2014]).weeksInYear(), 52, '2014 has 52 weeks');
-    assert.equal(moment([2015]).weeksInYear(), 52, '2015 has 53 weeks');
+    assert.equal(moment([2015]).weeksInYear(), 52, '2015 has 52 weeks');
+    assert.equal(moment([2016]).weeksInYear(), 52, '2016 has 52 weeks');
 });
 
 test('weeksInYear doy/dow = 0/6', function (assert) {