diff --git a/src/github.com/matrix-org/dendrite/clientapi/auth/auth.go b/src/github.com/matrix-org/dendrite/clientapi/auth/auth.go
index 80df0e728..a5a9b2bf9 100644
--- a/src/github.com/matrix-org/dendrite/clientapi/auth/auth.go
+++ b/src/github.com/matrix-org/dendrite/clientapi/auth/auth.go
@@ -72,7 +72,7 @@ func VerifyUserFromRequest(
 	}
 
 	// Try to find the Application Service user
-	token, err := extractAccessToken(req)
+	token, err := ExtractAccessToken(req)
 	if err != nil {
 		return nil, &util.JSONResponse{
 			Code: http.StatusUnauthorized,
@@ -150,7 +150,7 @@ func verifyUserParameters(req *http.Request) *util.JSONResponse {
 // and returns the device it corresponds to. Returns resErr (an error response which can be
 // sent to the client) if the token is invalid or there was a problem querying the database.
 func verifyAccessToken(req *http.Request, deviceDB DeviceDatabase) (device *authtypes.Device, resErr *util.JSONResponse) {
-	token, err := extractAccessToken(req)
+	token, err := ExtractAccessToken(req)
 	if err != nil {
 		resErr = &util.JSONResponse{
 			Code: http.StatusUnauthorized,
@@ -184,9 +184,9 @@ func GenerateAccessToken() (string, error) {
 	return base64.RawURLEncoding.EncodeToString(b), nil
 }
 
-// extractAccessToken from a request, or return an error detailing what went wrong. The
+// ExtractAccessToken from a request, or return an error detailing what went wrong. The
 // error message MUST be human-readable and comprehensible to the client.
-func extractAccessToken(req *http.Request) (string, error) {
+func ExtractAccessToken(req *http.Request) (string, error) {
 	// cf https://github.com/matrix-org/synapse/blob/v0.19.2/synapse/api/auth.py#L631
 	authBearer := req.Header.Get("Authorization")
 	queryToken := req.URL.Query().Get("access_token")
diff --git a/src/github.com/matrix-org/dendrite/clientapi/routing/register.go b/src/github.com/matrix-org/dendrite/clientapi/routing/register.go
index ee8259315..ef8577709 100644
--- a/src/github.com/matrix-org/dendrite/clientapi/routing/register.go
+++ b/src/github.com/matrix-org/dendrite/clientapi/routing/register.go
@@ -374,7 +374,13 @@ func validateApplicationService(
 ) (string, *util.JSONResponse) {
 	// Check if the token if the application service is valid with one we have
 	// registered in the config.
-	accessToken := req.URL.Query().Get("access_token")
+	accessToken, err := auth.ExtractAccessToken(req)
+	if err != nil {
+		return "", &util.JSONResponse{
+			Code: http.StatusUnauthorized,
+			JSON: jsonerror.MissingToken(err.Error()),
+		}
+	}
 	var matchedApplicationService *config.ApplicationService
 	for _, appservice := range cfg.Derived.ApplicationServices {
 		if appservice.ASToken == accessToken {
@@ -419,22 +425,6 @@ func validateApplicationService(
 	return matchedApplicationService.ID, nil
 }
 
-// authTypeIsValid checks the registration authentication type of the request
-// and returns true or false depending on whether the auth type is valid
-func authTypeIsValid(authType *authtypes.LoginType, req *http.Request) bool {
-	// If no auth type is specified by the client, send back the list of available flows
-	if *authType == "" && req.URL.Query().Get("access_token") != "" {
-		// Assume this is an application service registering a user if an empty login
-		// type was provided alongside an access token
-		*authType = authtypes.LoginTypeApplicationService
-	} else if *authType == "" {
-		// Not an access token, and no login type. Send back the flows
-		return false
-	}
-
-	return true
-}
-
 // Register processes a /register request.
 // http://matrix.org/speculator/spec/HEAD/client_server/unstable.html#post-matrix-client-unstable-register
 func Register(
@@ -474,16 +464,6 @@ func Register(
 		r.Username = strconv.FormatInt(id, 10)
 	}
 
-	// Check r.Auth.Type is correct for the client requesting (handles application
-	// services requesting without an auth type)
-	if !authTypeIsValid(&r.Auth.Type, req) {
-		return util.JSONResponse{
-			Code: http.StatusUnauthorized,
-			JSON: newUserInteractiveResponse(sessionID,
-				cfg.Derived.Registration.Flows, cfg.Derived.Registration.Params),
-		}
-	}
-
 	// Squash username to all lowercase letters
 	r.Username = strings.ToLower(r.Username)
 
@@ -562,7 +542,8 @@ func handleRegistrationFlow(
 		// Add SharedSecret to the list of completed registration stages
 		sessions.AddCompletedStage(sessionID, authtypes.LoginTypeSharedSecret)
 
-	case authtypes.LoginTypeApplicationService:
+	case "", authtypes.LoginTypeApplicationService:
+		// not passing a Auth.Type is allowed for ApplicationServices. So assume that as well
 		// Check application service register user request is valid.
 		// The application service's ID is returned if so.
 		appserviceID, err := validateApplicationService(cfg, req, r.Username)