diff --git a/registry/client.go b/registry/client.go
index 06e54a27f..b4cd7989f 100644
--- a/registry/client.go
+++ b/registry/client.go
@@ -66,7 +66,11 @@ func NewClient(services *disco.Disco, creds auth.CredentialsSource, client *http
 
 // Discover qeuries the host, and returns the url for the registry.
 func (c *Client) Discover(host svchost.Hostname) *url.URL {
-	return c.services.DiscoverServiceURL(host, serviceID)
+	service := c.services.DiscoverServiceURL(host, serviceID)
+	if !strings.HasSuffix(service.Path, "/") {
+		service.Path += "/"
+	}
+	return service
 }
 
 // Versions queries the registry for a module, and returns the available versions.
@@ -80,9 +84,6 @@ func (c *Client) Versions(module *regsrc.Module) (*response.ModuleVersions, erro
 	if service == nil {
 		return nil, fmt.Errorf("host %s does not provide Terraform modules", host)
 	}
-	if !strings.HasSuffix(service.Path, "/") {
-		service.Path += "/"
-	}
 
 	p, err := url.Parse(path.Join(module.Module(), "versions"))
 	if err != nil {
diff --git a/registry/test/mock_registry.go b/registry/test/mock_registry.go
index 844f569c6..c1fabbc25 100644
--- a/registry/test/mock_registry.go
+++ b/registry/test/mock_registry.go
@@ -23,7 +23,9 @@ import (
 // localhost.localdomain, and example.com to the test server.
 func Disco(s *httptest.Server) *disco.Disco {
 	services := map[string]interface{}{
-		"modules.v1": fmt.Sprintf("%s/v1/modules/", s.URL),
+		// Note that both with and without trailing slashes are supported behaviours
+		// TODO: add specific tests to enumerate both possibilities.
+		"modules.v1": fmt.Sprintf("%s/v1/modules", s.URL),
 	}
 	d := disco.NewDisco()