diff --git a/actix-codec/CHANGES.md b/actix-codec/CHANGES.md
index ae76143a..8959d057 100644
--- a/actix-codec/CHANGES.md
+++ b/actix-codec/CHANGES.md
@@ -1,5 +1,9 @@
 # Changes
 
+## [0.2.0-alpha.4]
+
+* Fix buffer remaining capacity calcualtion
+
 ## [0.2.0-alpha.3]
 
 * Use tokio 0.2
diff --git a/actix-codec/Cargo.toml b/actix-codec/Cargo.toml
index 67744c41..9f2f64b9 100644
--- a/actix-codec/Cargo.toml
+++ b/actix-codec/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "actix-codec"
-version = "0.2.0-alpha.3"
+version = "0.2.0-alpha.4"
 authors = ["Nikolay Kim <fafhrd91@gmail.com>"]
 description = "Utilities for encoding and decoding frames"
 keywords = ["network", "framework", "async", "futures"]
diff --git a/actix-codec/src/framed.rs b/actix-codec/src/framed.rs
index f4be2792..ed1ce7a1 100644
--- a/actix-codec/src/framed.rs
+++ b/actix-codec/src/framed.rs
@@ -2,7 +2,7 @@ use std::pin::Pin;
 use std::task::{Context, Poll};
 use std::{fmt, io};
 
-use bytes::{BufMut, BytesMut};
+use bytes::BytesMut;
 use futures::{ready, Sink, Stream};
 
 use crate::{AsyncRead, AsyncWrite, Decoder, Encoder};
@@ -208,7 +208,7 @@ impl<T, U> Framed<T, U> {
         T: AsyncWrite,
         U: Encoder,
     {
-        let remaining = self.write_buf.remaining_mut();
+        let remaining = self.write_buf.capacity() - self.write_buf.len();
         if remaining < LW {
             self.write_buf.reserve(HW - remaining);
         }
@@ -262,7 +262,7 @@ impl<T, U> Framed<T, U> {
             debug_assert!(!self.flags.contains(Flags::EOF));
 
             // Otherwise, try to read more data and try again. Make sure we've got room
-            let remaining = self.read_buf.remaining_mut();
+            let remaining = self.read_buf.capacity() - self.read_buf.len();
             if remaining < LW {
                 self.read_buf.reserve(HW - remaining)
             }