---
title: transactionId
framework: appstoreservernotifications
role: symbol
role_heading: Type
path: appstoreservernotifications/transactionid
---

# transactionId

The unique identifier for a transaction, such as an In-App Purchase, restored purchase, or subscription renewal.

## Declaration

```data
string transactionId
```

## Discussion

Discussion The App Store generates a new value for transaction identifier every time the subscription automatically renews or the user restores it on a new device. When a user first purchases a subscription, the transaction identifier always matches the original transaction identifier (originalTransactionId). For a restore or renewal, the transaction identifier doesn’t match the original transaction identifier. If a user restores or renews the same subscription multiple times, each restore or renewal has a unique transaction identifier.

## See Also

### Transaction identifiers

- [originalTransactionId](appstoreservernotifications/originaltransactionid.md)
- [webOrderLineItemId](appstoreservernotifications/weborderlineitemid.md)
- [previousOriginalTransactionId](appstoreservernotifications/previousoriginaltransactionid.md)