diff --git a/dist/amd/au-table.js b/dist/amd/au-table.js
index ec4718b..670879d 100644
--- a/dist/amd/au-table.js
+++ b/dist/amd/au-table.js
@@ -183,11 +183,14 @@ define(["exports", "aurelia-framework"], function (exports, _aureliaFramework) {
 
                     var key = _ref2;
 
-                    var value = next[key].toString();
 
-                    if (value.toLowerCase().indexOf(this.filterText.toLowerCase()) > -1) {
-                        filteredData.push(next);
-                        break;
+                    if (next[key] != null) {
+                        var value = next[key].toString().toLowerCase();
+
+                        if (value.indexOf(this.filterText.toLowerCase()) > -1) {
+                            filteredData.push(next);
+                            break;
+                        }
                     }
                 }
             }
diff --git a/dist/commonjs/au-table.js b/dist/commonjs/au-table.js
index 69e3bcf..727dfa9 100644
--- a/dist/commonjs/au-table.js
+++ b/dist/commonjs/au-table.js
@@ -180,11 +180,14 @@ var AureliaTableCustomAttribute = exports.AureliaTableCustomAttribute = (_dec =
 
                 var key = _ref2;
 
-                var value = next[key].toString();
 
-                if (value.toLowerCase().indexOf(this.filterText.toLowerCase()) > -1) {
-                    filteredData.push(next);
-                    break;
+                if (next[key] != null) {
+                    var value = next[key].toString().toLowerCase();
+
+                    if (value.indexOf(this.filterText.toLowerCase()) > -1) {
+                        filteredData.push(next);
+                        break;
+                    }
                 }
             }
         }
diff --git a/dist/es2015/au-table.js b/dist/es2015/au-table.js
index 882a1b5..c6e8cd0 100644
--- a/dist/es2015/au-table.js
+++ b/dist/es2015/au-table.js
@@ -140,11 +140,14 @@ export let AureliaTableCustomAttribute = (_dec = inject(BindingEngine), _dec2 =
 
         for (let next of toFilter) {
             for (let key of this.filterKeys) {
-                let value = next[key].toString();
 
-                if (value.toLowerCase().indexOf(this.filterText.toLowerCase()) > -1) {
-                    filteredData.push(next);
-                    break;
+                if (next[key] != null) {
+                    let value = next[key].toString().toLowerCase();
+
+                    if (value.indexOf(this.filterText.toLowerCase()) > -1) {
+                        filteredData.push(next);
+                        break;
+                    }
                 }
             }
         }
diff --git a/dist/system/au-table.js b/dist/system/au-table.js
index e81d922..76aca7f 100644
--- a/dist/system/au-table.js
+++ b/dist/system/au-table.js
@@ -188,11 +188,14 @@ System.register(["aurelia-framework"], function (_export, _context) {
 
                             var key = _ref2;
 
-                            var value = next[key].toString();
 
-                            if (value.toLowerCase().indexOf(this.filterText.toLowerCase()) > -1) {
-                                filteredData.push(next);
-                                break;
+                            if (next[key] != null) {
+                                var value = next[key].toString().toLowerCase();
+
+                                if (value.indexOf(this.filterText.toLowerCase()) > -1) {
+                                    filteredData.push(next);
+                                    break;
+                                }
                             }
                         }
                     }
diff --git a/src/au-table.js b/src/au-table.js
index 796f997..4124dc8 100644
--- a/src/au-table.js
+++ b/src/au-table.js
@@ -101,14 +101,17 @@ export class AureliaTableCustomAttribute {
 
     doFilter(toFilter) {
         let filteredData = [];
-
+        
         for (let next of toFilter) {
             for (let key of this.filterKeys) {
-                let value = next[key].toString();
 
-                if (value.toLowerCase().indexOf(this.filterText.toLowerCase()) > -1) {
-                    filteredData.push(next);
-                    break;
+                if( next[key]!= null ){
+                    let value = next[key].toString().toLowerCase();
+
+                    if (value.indexOf(this.filterText.toLowerCase()) > -1) {
+                        filteredData.push(next);
+                        break;
+                    }
                 }
             }
         }