diff --git a/const_bsds.go b/const_bsds.go
index 28cd274..9717374 100644
--- a/const_bsds.go
+++ b/const_bsds.go
@@ -11,7 +11,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-// +build darwin openbsd
+// +build darwin openbsd freebsd
 
 package afero
 
diff --git a/const_win_unix.go b/const_win_unix.go
index 72d6aaf..d8f392b 100644
--- a/const_win_unix.go
+++ b/const_win_unix.go
@@ -12,6 +12,7 @@
 // limitations under the License.
 // +build !darwin
 // +build !openbsd
+// +build !freebsd
 
 package afero