diff --git a/builtin/providers/cloudstack/config.go b/builtin/providers/cloudstack/config.go
index b7c4c7ce1..9185bb27e 100644
--- a/builtin/providers/cloudstack/config.go
+++ b/builtin/providers/cloudstack/config.go
@@ -8,11 +8,12 @@ type Config struct {
 	ApiURL    string
 	ApiKey    string
 	SecretKey string
+	Timeout   int64
 }
 
 // Client() returns a new CloudStack client.
 func (c *Config) NewClient() (*cloudstack.CloudStackClient, error) {
 	cs := cloudstack.NewAsyncClient(c.ApiURL, c.ApiKey, c.SecretKey, false)
-	cs.AsyncTimeout(180)
+	cs.AsyncTimeout(c.Timeout)
 	return cs, nil
 }
diff --git a/builtin/providers/cloudstack/provider.go b/builtin/providers/cloudstack/provider.go
index 6440ff2c0..f00f11cb7 100644
--- a/builtin/providers/cloudstack/provider.go
+++ b/builtin/providers/cloudstack/provider.go
@@ -14,19 +14,25 @@ func Provider() terraform.ResourceProvider {
 			"api_url": &schema.Schema{
 				Type:        schema.TypeString,
 				Required:    true,
-				DefaultFunc: envDefaultFunc("CLOUDSTACK_API_URL"),
+				DefaultFunc: envDefaultFunc("CLOUDSTACK_API_URL", nil),
 			},
 
 			"api_key": &schema.Schema{
 				Type:        schema.TypeString,
 				Required:    true,
-				DefaultFunc: envDefaultFunc("CLOUDSTACK_API_KEY"),
+				DefaultFunc: envDefaultFunc("CLOUDSTACK_API_KEY", nil),
 			},
 
 			"secret_key": &schema.Schema{
 				Type:        schema.TypeString,
 				Required:    true,
-				DefaultFunc: envDefaultFunc("CLOUDSTACK_SECRET_KEY"),
+				DefaultFunc: envDefaultFunc("CLOUDSTACK_SECRET_KEY", nil),
+			},
+
+			"timeout": &schema.Schema{
+				Type:        schema.TypeInt,
+				Required:    true,
+				DefaultFunc: envDefaultFunc("CLOUDSTACK_TIMEOUT", 180),
 			},
 		},
 
@@ -52,17 +58,18 @@ func providerConfigure(d *schema.ResourceData) (interface{}, error) {
 		ApiURL:    d.Get("api_url").(string),
 		ApiKey:    d.Get("api_key").(string),
 		SecretKey: d.Get("secret_key").(string),
+		Timeout:   d.Get("timeout").(int64),
 	}
 
 	return config.NewClient()
 }
 
-func envDefaultFunc(k string) schema.SchemaDefaultFunc {
+func envDefaultFunc(k string, dv interface{}) schema.SchemaDefaultFunc {
 	return func() (interface{}, error) {
 		if v := os.Getenv(k); v != "" {
 			return v, nil
 		}
 
-		return nil, nil
+		return dv, nil
 	}
 }