diff --git a/README.dev.md b/README.dev.md
index 20c72ace59..40dd6bfb7d 100644
--- a/README.dev.md
+++ b/README.dev.md
@@ -841,13 +841,22 @@ it (with the appropriate values in it for your proxy):
 HTTP_PROXY http://proxy_host:port
 HTTPS_PROXY http://proxy_host:port
 NO_PROXY localhost,127.0.0.1,.example.com
-
 ```
 
 Now run `vagrant up` in your terminal to install the development
 server. If you ran `vagrant up` before and failed, you'll need to run
 `vagrant destroy` first to clean up the failed installation.
 
+You can also change the port on the host machine that Vagrant uses by
+adding to your `~/.zulip-vagrant-config` file.  E.g. if you set:
+
+```
+HOST_PORT 9971
+```
+
+(and halt and restart the Vagrant guest), then you would visit
+http://localhost:9971/ to connect to your development server.
+
 Installing on Ubuntu 14.04 Trusty without Vagrant
 ----------------------------------
 Start by cloning this repository: `git clone
diff --git a/Vagrantfile b/Vagrantfile
index fb24b5070e..73ddf23c5a 100644
--- a/Vagrantfile
+++ b/Vagrantfile
@@ -13,16 +13,15 @@ Vagrant.configure(VAGRANTFILE_API_VERSION) do |config|
   config.vm.box = "fgrehm/trusty64-lxc"
 
   # The Zulip development environment runs on 9991 on the guest.
-  config.vm.network "forwarded_port", guest: 9991, host: 9991, host_ip: "127.0.0.1"
+  host_port = 9991
+  http_proxy = https_proxy = no_proxy = ""
 
   config.vm.synced_folder ".", "/vagrant", disabled: true
   config.vm.synced_folder ".", "/srv/zulip"
 
-  proxy_config_file = ENV['HOME'] + "/.zulip-vagrant-config"
-  if File.file?(proxy_config_file)
-    http_proxy = https_proxy = no_proxy = ""
-
-    IO.foreach(proxy_config_file) do |line|
+  vagrant_config_file = ENV['HOME'] + "/.zulip-vagrant-config"
+  if File.file?(vagrant_config_file)
+    IO.foreach(vagrant_config_file) do |line|
       line.chomp!
       key, value = line.split(nil, 2)
       case key
@@ -30,19 +29,22 @@ Vagrant.configure(VAGRANTFILE_API_VERSION) do |config|
       when "HTTP_PROXY"; http_proxy = value
       when "HTTPS_PROXY"; https_proxy = value
       when "NO_PROXY"; no_proxy = value
+      when "HOST_PORT"; host_port = value.to_i
       end
     end
+  end
 
-    if Vagrant.has_plugin?("vagrant-proxyconf")
-      if http_proxy != ""
-        config.proxy.http = http_proxy
-      end
-      if https_proxy != ""
-        config.proxy.https = https_proxy
-      end
-      if https_proxy != ""
-        config.proxy.no_proxy = no_proxy
-      end
+  config.vm.network "forwarded_port", guest: 9991, host: host_port, host_ip: "127.0.0.1"
+
+  if Vagrant.has_plugin?("vagrant-proxyconf")
+    if http_proxy != ""
+      config.proxy.http = http_proxy
+    end
+    if https_proxy != ""
+      config.proxy.https = https_proxy
+    end
+    if https_proxy != ""
+      config.proxy.no_proxy = no_proxy
     end
   end