diff --git a/api/api.go b/api/api.go
index c418cd2293..7ed8532941 100644
--- a/api/api.go
+++ b/api/api.go
@@ -71,6 +71,10 @@ const (
 	// client in this package but is defined here for consistency with all the
 	// other ENV names we use.
 	GRPCAddrEnvName = "CONSUL_GRPC_ADDR"
+
+	// HTTPNamespaceEnvVar defines an environment variable name which sets
+	// the HTTP Namespace to be used by default. This can still be overridden.
+	HTTPNamespaceEnvName = "CONSUL_NAMESPACE"
 )
 
 // QueryOptions are used to parameterize a query
@@ -427,6 +431,10 @@ func defaultConfig(transportFn func() *http.Transport) *Config {
 		}
 	}
 
+	if v := os.Getenv(HTTPNamespaceEnvName); v != "" {
+		config.Namespace = v
+	}
+
 	return config
 }
 
diff --git a/command/flags/http.go b/command/flags/http.go
index c473dc1d0e..947c5947d9 100644
--- a/command/flags/http.go
+++ b/command/flags/http.go
@@ -76,8 +76,7 @@ func (f *HTTPFlags) ServerFlags() *flag.FlagSet {
 
 func (f *HTTPFlags) NamespaceFlags() *flag.FlagSet {
 	fs := flag.NewFlagSet("", flag.ContinueOnError)
-	// TODO (namespaces) Do we want to allow setting via an env var? CONSUL_NAMESPACE
-	fs.Var(&f.namespace, "ns",
+	fs.Var(&f.namespace, "namespace",
 		"Specifies the namespace to query. If not provided, the namespace will"+
 			"default to the `default` namespace. Namespaces is a Consul Enterprise feature.")
 	return fs
diff --git a/website/source/docs/commands/_http_api_namespace_options.html.md b/website/source/docs/commands/_http_api_namespace_options.html.md
index 76a28d0c46..2a33ef5ee0 100644
--- a/website/source/docs/commands/_http_api_namespace_options.html.md
+++ b/website/source/docs/commands/_http_api_namespace_options.html.md
@@ -1,2 +1,3 @@
-* `-ns=<string>` - Specifies the namespace to query. If not provided, the namespace
-  will default to the `default` namespace. Namespaces is a Consul Enterprise feature added in v1.7.0.
+* `-namespace=<string>` - Specifies the namespace to query. If not provided, the namespace will default
+  to the value of the `CONSUL_NAMESPACE` environment variable or `default` if neither is set. Namespaces 
+  is a Consul Enterprise feature added in v1.7.0.