diff --git a/src/main/java/com/ethlo/time/DateTime.java b/src/main/java/com/ethlo/time/DateTime.java
index 5d38005..a890670 100644
--- a/src/main/java/com/ethlo/time/DateTime.java
+++ b/src/main/java/com/ethlo/time/DateTime.java
@@ -444,12 +444,12 @@ private String toString(final DateTime date, final Field lastIncluded, final int
         }
 
         // Fractions
-        if (lastIncluded.ordinal() >= Field.NANO.ordinal())
+        if (fractionDigits > 0 && lastIncluded.ordinal() >= Field.NANO.ordinal())
         {
             buffer[19] = '.';
             LimitedCharArrayIntegerUtil.toString(date.getNano(), buffer, 20, fractionDigits);
         }
-        return finish(buffer, 20 + fractionDigits, tz);
+        return finish(buffer, 19 + (fractionDigits > 0 ? 1 : 0) + fractionDigits, tz);
     }
 
     /**
diff --git a/src/test/java/com/ethlo/time/FormatterTest.java b/src/test/java/com/ethlo/time/FormatterTest.java
index f4d24c3..6d0cd19 100644
--- a/src/test/java/com/ethlo/time/FormatterTest.java
+++ b/src/test/java/com/ethlo/time/FormatterTest.java
@@ -120,4 +120,11 @@ void testFormat5()
         final OffsetDateTime date = ITU.parseDateTime(s);
         assertThat(ITU.formatUtcMilli(date)).isEqualTo("2017-02-21T02:27:39.123Z");
     }
+
+    @Test
+    void testTostring()
+    {
+        final DateTime dateTime = DateTime.of(2000,12, 31, 22, 30, 0, 0,null, 0);
+        assertThat(dateTime.toString()).isEqualTo("2000-12-31T22:30:00");
+    }
 }