<!--
{
  "availability" : [
    "iOS: 13.0.0 -",
    "iPadOS: 13.0.0 -",
    "macCatalyst: 13.1.0 -"
  ],
  "documentType" : "symbol",
  "framework" : "CoreNFC",
  "identifier" : "/documentation/CoreNFC/NFCTagReaderSession/restartPolling()",
  "metadataVersion" : "0.1.0",
  "role" : "Instance Method",
  "symbol" : {
    "kind" : "Instance Method",
    "modules" : [
      "Core NFC"
    ],
    "preciseIdentifier" : "c:objc(cs)NFCTagReaderSession(im)restartPolling"
  },
  "title" : "restartPolling()"
}
-->

# restartPolling()

Restarts the polling sequence so the reader session can discover new tags.

```
func restartPolling()
```

## Discussion

After restarting the polling sequence, the reader session sends newly detected tags to the session’s delegate method [`tagReaderSession(_:didDetect:)`](/documentation/CoreNFC/NFCTagReaderSessionDelegate-2joku/tagReaderSession(_:didDetect:)).

> Note:
> Tags detected before polling restarts are invalid. Your app should discard any references it has to the invalid tags to free system resources.

Calling [`restartPolling()`](/documentation/CoreNFC/NFCTagReaderSession/restartPolling()) on an invalidated session has no effect. If you need to restart the reader session, create a new [`NFCTagReaderSession`](/documentation/CoreNFC/NFCTagReaderSession).

---

Copyright &copy; 2026 Apple Inc. All rights reserved. | [Terms of Use](https://www.apple.com/legal/internet-services/terms/site.html) | [Privacy Policy](https://www.apple.com/privacy/privacy-policy)