How to generate unique IDs for Gravity Forms submissions

Decide whether the built-in entry ID is enough or whether you need a customer-facing reference such as REF-000123. The built-in entry ID is unique across the site’s Gravity Forms entries, but it is not a separate sequence for each form and cannot be given a prefix through the normal form settings.

Use the entry ID for a simple internal reference. Use a custom ID when people must read it, when each form needs its own numbering, or when you need alphanumeric formatting.

For the manual route, open the form’s confirmation or notification settings and insert {entry_id} where the reference number should appear. Gravity Forms makes this merge tag available after the entry has been saved, so it works in confirmations and notifications but not as a field’s default value.

Submit the form once and check both the confirmation and the email. Remember that this number is the database entry ID: it is sequential across all forms on the site, so unrelated forms can consume numbers between two submissions of your form.

If you need the ID stored in a form field, add a hidden field and use the gform_entry_post_save filter to build the value from the saved entry ID. For example, a developer can create a value such as REF- followed by the entry ID, then save it with GFAPI::update_entry_field(). Gravity Forms documents both the post-save filter and the API method for updating an entry field.

Replace the form and field IDs in the code with your own, and test it on staging first. This approach gives you a site-wide unique value derived from the entry ID, but it does not provide an independent per-form counter. Do not calculate the next number by counting existing entries: deleted entries, imports, concurrent submissions, and failed attempts can create gaps or duplicates.

For a configurable ID, install and activate the Gravity Perks Unique ID Plugin, then edit the form and add its Unique ID field. Choose Sequential for a counting reference, Numeric for digits only, or Alphanumeric for a mixed value. Sequential IDs are generated per field and can be configured with a starting number, length, prefix, and suffix.

This is the fast route when you need a form-specific sequence or a format such as CASE-00125. It avoids maintaining custom PHP and provides the generated value as a normal field that can be used with Gravity Forms merge tags.

In the confirmation and notification settings, use the field merge-tag picker to insert the Unique ID field. Field merge tags use the field label and field ID, for example {Reference:5}; using the picker avoids mistakes when the field ID is different on your form.

Submit two test entries and confirm that the values are different, appear in the entry list, and arrive in the expected email or confirmation. Test a failed validation, a resubmission, and any payment or approval workflow separately. The common Friday problem is displaying the ID in an email but forgetting to store or display the same field in the admin entry.