diff --git a/futures-util/src/io/buf_reader.rs b/futures-util/src/io/buf_reader.rs
index deff1044ac..e0acdc9950 100644
--- a/futures-util/src/io/buf_reader.rs
+++ b/futures-util/src/io/buf_reader.rs
@@ -39,20 +39,7 @@ pin_project! {
     }
 }
 
-impl<R: AsyncRead> BufReader<R> {
-    /// Creates a new `BufReader` with a default buffer capacity. The default is currently 8 KB,
-    /// but may change in the future.
-    pub fn new(inner: R) -> Self {
-        Self::with_capacity(DEFAULT_BUF_SIZE, inner)
-    }
-
-    /// Creates a new `BufReader` with the specified buffer capacity.
-    pub fn with_capacity(capacity: usize, inner: R) -> Self {
-        // TODO: consider using Box<[u8]>::new_uninit_slice once it stabilized
-        let buffer = vec![0; capacity];
-        Self { inner, buffer: buffer.into_boxed_slice(), pos: 0, cap: 0 }
-    }
-
+impl<R> BufReader<R> {
     delegate_access_inner!(inner, R, ());
 
     /// Returns a reference to the internally buffered data.
@@ -71,6 +58,21 @@ impl<R: AsyncRead> BufReader<R> {
     }
 }
 
+impl<R: AsyncRead> BufReader<R> {
+    /// Creates a new `BufReader` with a default buffer capacity. The default is currently 8 KB,
+    /// but may change in the future.
+    pub fn new(inner: R) -> Self {
+        Self::with_capacity(DEFAULT_BUF_SIZE, inner)
+    }
+
+    /// Creates a new `BufReader` with the specified buffer capacity.
+    pub fn with_capacity(capacity: usize, inner: R) -> Self {
+        // TODO: consider using Box<[u8]>::new_uninit_slice once it stabilized
+        let buffer = vec![0; capacity];
+        Self { inner, buffer: buffer.into_boxed_slice(), pos: 0, cap: 0 }
+    }
+}
+
 impl<R: AsyncRead + AsyncSeek> BufReader<R> {
     /// Seeks relative to the current position. If the new position lies within the buffer,
     /// the buffer will not be flushed, allowing for more efficient seeks.
diff --git a/futures-util/src/io/buf_writer.rs b/futures-util/src/io/buf_writer.rs
index e0037262b9..83ddcceadf 100644
--- a/futures-util/src/io/buf_writer.rs
+++ b/futures-util/src/io/buf_writer.rs
@@ -39,6 +39,61 @@ pin_project! {
     }
 }
 
+impl<W> BufWriter<W> {
+    delegate_access_inner!(inner, W, ());
+
+    /// Returns a reference to the internally buffered data.
+    pub fn buffer(&self) -> &[u8] {
+        &self.buf
+    }
+
+    /// Capacity of `buf`. how many chars can be held in buffer
+    pub(super) fn capacity(&self) -> usize {
+        self.buf.capacity()
+    }
+
+    /// Remaining number of bytes to reach `buf` 's capacity
+    #[inline]
+    pub(super) fn spare_capacity(&self) -> usize {
+        self.buf.capacity() - self.buf.len()
+    }
+
+    /// Write byte slice directly into `self.buf`
+    ///
+    /// Based on `std::io::BufWriter`
+    #[inline]
+    unsafe fn write_to_buffer_unchecked(self: Pin<&mut Self>, buf: &[u8]) {
+        debug_assert!(buf.len() <= self.spare_capacity());
+        let this = self.project();
+        let old_len = this.buf.len();
+        let buf_len = buf.len();
+        let src = buf.as_ptr();
+        unsafe {
+            let dst = this.buf.as_mut_ptr().add(old_len);
+            ptr::copy_nonoverlapping(src, dst, buf_len);
+            this.buf.set_len(old_len + buf_len);
+        }
+    }
+
+    /// Write a byte slice directly into buffer
+    ///
+    /// Will truncate the number of bytes written to `spare_capacity()` so you want to
+    /// calculate the size of your slice to avoid losing bytes
+    ///
+    /// Based on `std::io::BufWriter`
+    pub(super) fn write_to_buf(self: Pin<&mut Self>, buf: &[u8]) -> usize {
+        let available = self.spare_capacity();
+        let amt_to_buffer = available.min(buf.len());
+
+        // SAFETY: `amt_to_buffer` is <= buffer's spare capacity by construction.
+        unsafe {
+            self.write_to_buffer_unchecked(&buf[..amt_to_buffer]);
+        }
+
+        amt_to_buffer
+    }
+}
+
 impl<W: AsyncWrite> BufWriter<W> {
     /// Creates a new `BufWriter` with a default buffer capacity. The default is currently 8 KB,
     /// but may change in the future.
@@ -79,59 +134,6 @@ impl<W: AsyncWrite> BufWriter<W> {
         Poll::Ready(ret)
     }
 
-    delegate_access_inner!(inner, W, ());
-
-    /// Returns a reference to the internally buffered data.
-    pub fn buffer(&self) -> &[u8] {
-        &self.buf
-    }
-
-    /// Capacity of `buf`. how many chars can be held in buffer
-    pub(super) fn capacity(&self) -> usize {
-        self.buf.capacity()
-    }
-
-    /// Remaining number of bytes to reach `buf` 's capacity
-    #[inline]
-    pub(super) fn spare_capacity(&self) -> usize {
-        self.buf.capacity() - self.buf.len()
-    }
-
-    /// Write a byte slice directly into buffer
-    ///
-    /// Will truncate the number of bytes written to `spare_capacity()` so you want to
-    /// calculate the size of your slice to avoid losing bytes
-    ///
-    /// Based on `std::io::BufWriter`
-    pub(super) fn write_to_buf(self: Pin<&mut Self>, buf: &[u8]) -> usize {
-        let available = self.spare_capacity();
-        let amt_to_buffer = available.min(buf.len());
-
-        // SAFETY: `amt_to_buffer` is <= buffer's spare capacity by construction.
-        unsafe {
-            self.write_to_buffer_unchecked(&buf[..amt_to_buffer]);
-        }
-
-        amt_to_buffer
-    }
-
-    /// Write byte slice directly into `self.buf`
-    ///
-    /// Based on `std::io::BufWriter`
-    #[inline]
-    unsafe fn write_to_buffer_unchecked(self: Pin<&mut Self>, buf: &[u8]) {
-        debug_assert!(buf.len() <= self.spare_capacity());
-        let this = self.project();
-        let old_len = this.buf.len();
-        let buf_len = buf.len();
-        let src = buf.as_ptr();
-        unsafe {
-            let dst = this.buf.as_mut_ptr().add(old_len);
-            ptr::copy_nonoverlapping(src, dst, buf_len);
-            this.buf.set_len(old_len + buf_len);
-        }
-    }
-
     /// Write directly using `inner`, bypassing buffering
     pub(super) fn inner_poll_write(
         self: Pin<&mut Self>,