diff --git a/Source/WebSocket.swift b/Source/WebSocket.swift
index a6dcbb01..200dc920 100644
--- a/Source/WebSocket.swift
+++ b/Source/WebSocket.swift
@@ -203,6 +203,7 @@ open class WebSocket : NSObject, StreamDelegate {
      - Parameter closeCode: The code to send on disconnect. The default is the normal close code for cleanly disconnecting a webSocket.
     */
     open func disconnect(forceTimeout: TimeInterval? = nil, closeCode: UInt16 = CloseCode.normal.rawValue) {
+        guard isConnected else { return }
         switch forceTimeout {
         case .some(let seconds) where seconds > 0:
             let milliseconds = Int(seconds * 1_000)