diff --git a/lib/client.js b/lib/client.js
index 84c527201..544fbf9d5 100644
--- a/lib/client.js
+++ b/lib/client.js
@@ -2277,6 +2277,54 @@ MatrixClient.prototype.getFilter = function(userId, filterId, allowCached) {
     });
 };
 
+/**
+ * @param {string} filterName
+ * @param {Filter} filter
+ * @return {Promise<String>} Filter ID
+ */
+MatrixClient.prototype.getOrCreateFilter = function(filterName, filter) {
+
+    var filterId = this.store.getFilterIdByName(filterName);
+    var promise = q();
+    var self = this;
+
+    if (filterId) {
+        // check that the existing filter matches our expectations
+        promise = self.getFilter(self.credentials.userId,
+                         filterId, true
+        ).then(function(existingFilter) {
+            var oldDef = existingFilter.getDefinition();
+            var newDef = filter.getDefinition();
+
+            if (utils.deepCompare(oldDef, newDef)) {
+                // super, just use that.
+                // debuglog("Using existing filter ID %s: %s", filterId,
+                //          JSON.stringify(oldDef));
+                return q(filterId);
+            }
+            // debuglog("Existing filter ID %s: %s; new filter: %s",
+            //          filterId, JSON.stringify(oldDef), JSON.stringify(newDef));
+            return;
+        });
+    }
+
+    return promise.then(function(existingId) {
+        if (existingId) {
+            return existingId;
+        }
+
+        // create a new filter
+        return self.createFilter(filter.getDefinition()
+        ).then(function(createdFilter) {
+            // debuglog("Created new filter ID %s: %s", createdFilter.filterId,
+            //          JSON.stringify(createdFilter.getDefinition()));
+            self.store.setFilterIdByName(filterName, createdFilter.filterId);
+            return createdFilter.filterId;
+        });
+    });
+};
+
+
 /**
  * Gets a bearer token from the Home Server that the user can
  * present to a third party in order to prove their ownership
diff --git a/lib/sync.js b/lib/sync.js
index 91bb0cc51..870c83597 100644
--- a/lib/sync.js
+++ b/lib/sync.js
@@ -148,7 +148,7 @@ SyncApi.prototype.syncLeftRooms = function() {
         timeout: 0 // don't want to block since this is a single isolated req
     };
 
-    return this._getOrCreateFilter(
+    return client.getOrCreateFilter(
         getFilterName(client.credentials.userId, "LEFT_ROOMS"), filter
     ).then(function(filterId) {
         qps.filter = filterId;
@@ -389,7 +389,7 @@ SyncApi.prototype.sync = function() {
         var filter = new Filter(client.credentials.userId);
         filter.setTimelineLimit(self.opts.initialSyncLimit);
 
-        self._getOrCreateFilter(
+        client.getOrCreateFilter(
             getFilterName(client.credentials.userId), filter
         ).done(function(filterId) {
             self._sync({ filterId: filterId });
@@ -837,53 +837,6 @@ SyncApi.prototype._pokeKeepAlive = function() {
     });
 };
 
-/**
- * @param {string} filterName
- * @param {Filter} filter
- * @return {Promise<String>} Filter ID
- */
-SyncApi.prototype._getOrCreateFilter = function(filterName, filter) {
-    var client = this.client;
-
-    var filterId = client.store.getFilterIdByName(filterName);
-    var promise = q();
-
-    if (filterId) {
-        // check that the existing filter matches our expectations
-        promise = client.getFilter(client.credentials.userId,
-                         filterId, true
-        ).then(function(existingFilter) {
-            var oldDef = existingFilter.getDefinition();
-            var newDef = filter.getDefinition();
-
-            if (utils.deepCompare(oldDef, newDef)) {
-                // super, just use that.
-                debuglog("Using existing filter ID %s: %s", filterId,
-                         JSON.stringify(oldDef));
-                return q(filterId);
-            }
-            debuglog("Existing filter ID %s: %s; new filter: %s",
-                     filterId, JSON.stringify(oldDef), JSON.stringify(newDef));
-            return;
-        });
-    }
-
-    return promise.then(function(existingId) {
-        if (existingId) {
-            return existingId;
-        }
-
-        // create a new filter
-        return client.createFilter(filter.getDefinition()
-        ).then(function(createdFilter) {
-            debuglog("Created new filter ID %s: %s", createdFilter.filterId,
-                     JSON.stringify(createdFilter.getDefinition()));
-            client.store.setFilterIdByName(filterName, createdFilter.filterId);
-            return createdFilter.filterId;
-        });
-    });
-};
-
 /**
  * @param {Object} obj
  * @return {Object[]}