HelpCreateBasics of creating a Zap

Data deduplication in Zaps

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Duplicate data is handled differently in Zap triggers and actions.


Zapier relies on a few methods to make sure that your Zap does not trigger multiple times for a single "new" item.

The way Zapier does this is generally by polling, looking for new items every few minutes (your plan's polling interval). Zapier stores an identifier for each item seen so that the Zap never triggers off of that item again.


If you have two Zaps using the same trigger (e.g. two Zaps which trigger off the same form) both Zaps will be triggered by new items. Deduplication happens on a per-Zap basis.

Deduplication has several important effects:

  • Once Zapier has seen an item for a Zap, it will never trigger again—even if the item is updated in the future.
  • Trigger filters are applied before deduplication happens. You can use regular filters to catch "changes". For example, using the "new note" Evernote trigger and choosing a specific tag to watch via regular filters would trigger even if you applied the tag one day after the note was originally created.
  • Custom filters are applied after deduplication happens. You can't use a custom filter to trigger when an item changes. For example, a #hashtag applied to an Evernote title one day after the note was originally created would not work.

The following apps and triggers have a special "steady-state" post-deduplication process applied. Normally, a new item will trigger a Zap as soon as Zapier first encounters it. However, this is not ideal for certain items that are created before you finish setting them up.


For example, you might still be typing into your new Evernote note when it triggers your Zap. The steady-state postprocessor will wait to trigger a Zap until the item has stopped changing across one polling interval.

  • Evernote New Notes
  • Trello New Cards
  • Magento New Sales Orders


Depending on the app, actions can result in several outcomes if your Zap is trying to create data that already exists in that app:

  • Duplication: some apps allow for duplicate records. In those cases, the Zap will create duplicates.
  • Errors: some apps will return an error message, which can be viewed in the Zap History.
  • Updates: on rare occasions, Zapier may be able to update duplicate records with data from the Zap. It's important to note that updating can often mean overwriting. You should check if there is information in the action app that you might potentially lose.
  • Stop/Ignore: on rare occasions, the Zap will attempt to add a duplicate, but the action app will recognize the duplicate and take no action.

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