diff --git a/src/Validator/IsFloat.php b/src/Validator/IsFloat.php
index 0c29774a..07556ec2 100644
--- a/src/Validator/IsFloat.php
+++ b/src/Validator/IsFloat.php
@@ -235,7 +235,9 @@ public function isValid($value)
         // No strrpos() in wrappers yet. ICU 4.x doesn't have grouping size for
         // everything. ICU 52 has 3 for ALL locales.
         $groupSize = $formatter->getAttribute(NumberFormatter::GROUPING_SIZE) ?: 3;
-        $lastStringGroup = $this->wrapper->substr($value, -$groupSize);
+        $lastStringGroup = $this->wrapper->strlen($value) > $groupSize ?
+            $this->wrapper->substr($value, -$groupSize) :
+            $value;
 
         if ((preg_match($lnumSearch, $unGroupedValue)
             || preg_match($dnumSearch, $unGroupedValue)
diff --git a/test/Validator/IsFloatTest.php b/test/Validator/IsFloatTest.php
index 0073f6e1..e7a84ae1 100644
--- a/test/Validator/IsFloatTest.php
+++ b/test/Validator/IsFloatTest.php
@@ -73,7 +73,7 @@ public function floatAndIntegerProvider()
         $trueArray       = [];
         $testingLocales  = ['ar', 'bn', 'de', 'dz', 'en', 'fr-CH', 'ja', 'ks', 'ml-IN', 'mr', 'my', 'ps', 'ru'];
         $testingExamples = [1000, -2000, +398.00, 0.04, -0.5, .6, -.70, 8E10, -9.3456E-2, 10.23E6,
-            123.1234567890987654321];
+            123.1234567890987654321, 1, 13, -3];
 
         //Loop locales and examples for a more thorough set of "true" test data
         foreach ($testingLocales as $locale) {