diff --git a/clientapi/clientapi.go b/clientapi/clientapi.go
index 5b6e21c80..b891f046c 100644
--- a/clientapi/clientapi.go
+++ b/clientapi/clientapi.go
@@ -44,6 +44,17 @@ func SetupClientAPIComponent(
 	asAPI appserviceAPI.AppServiceQueryAPI,
 	transactionsCache *transactions.Cache,
 ) {
+	if base.Cfg.Matrix.RecaptchaEnabled &&
+		(base.Cfg.Matrix.RecaptchaPublicKey == "" ||
+		base.Cfg.Matrix.RecaptchaPrivateKey == "" ||
+		base.Cfg.Matrix.RecaptchaSiteVerifyAPI == "") {
+		logrus.Panicf(
+			"Recaptcha configs are missing. " +
+				"Ensure that recaptcha_public_key, recaptcha_private_key and " +
+				"recaptcha_siteverify_api are specified",
+		)
+	}
+
 	roomserverProducer := producers.NewRoomserverProducer(inputAPI)
 	typingProducer := producers.NewTypingServerProducer(typingInputAPI)