diff --git a/pkgpanda/util.py b/pkgpanda/util.py
index bd0c77102b..701cc97047 100644
--- a/pkgpanda/util.py
+++ b/pkgpanda/util.py
@@ -11,6 +11,7 @@
 import subprocess
 import tarfile
 import tempfile
+import time
 from contextlib import contextmanager, ExitStack
 from itertools import chain
 from multiprocessing import Process
@@ -150,6 +151,38 @@ def get_requests_retry_session(max_retries=4, backoff_factor=1, status_forcelist
     return session
 
 
+def stream_remote_file_with_retries(out_filename, url, retries=4):
+    def cleanup():
+        try:
+            os.remove(out_filename)
+        except Exception:
+            pass
+
+    while True:
+        with open(out_filename, "w+b") as f:
+            r = get_requests_retry_session().get(url, stream=True)
+            if r.status_code == 301:
+                raise Exception("got a 301")
+            r.raise_for_status()
+
+            for chunk in r.iter_content(chunk_size=4096):
+                f.write(chunk)
+            f.flush()
+
+            content_length = int(r.headers['content-length'])
+            final_size = os.fstat(f.fileno()).st_size
+            if final_size == content_length:
+                return r
+            else:
+                f.close()
+                cleanup()
+                retries -= 1
+                if retries <= 0:
+                    raise Exception("final file size does not match Content-Length")
+                time.sleep(2 ** (3 - retries))
+                continue
+
+
 def download(out_filename, url, work_dir, rm_on_error=True):
     assert os.path.isabs(out_filename)
     assert os.path.isabs(work_dir)
@@ -167,14 +200,7 @@ def download(out_filename, url, work_dir, rm_on_error=True):
                 src_filename = work_dir + '/' + src_filename
             shutil.copyfile(src_filename, out_filename)
         else:
-            # Download the file.
-            with open(out_filename, "w+b") as f:
-                r = get_requests_retry_session().get(url, stream=True)
-                if r.status_code == 301:
-                    raise Exception("got a 301")
-                r.raise_for_status()
-                for chunk in r.iter_content(chunk_size=4096):
-                    f.write(chunk)
+            stream_remote_file_with_retries(out_filename, url)
     except Exception as fetch_exception:
         if rm_on_error:
             rm_passed = False