---
title: Manage cookies for Forms
slug: cms-12/docs/managing-cookies
docTags: 
createdAt: 2026-08-10T15:55:55.000Z
---

:::hint{type="info"}
**Note**
[Optimizely Forms](docId:3SbSlJZIS_3iFmghfQA3J) is only supported by MVC-based websites and HTML5-compliant browsers.
:::

## Cookie usage in Optimizely Forms

Optimizely Forms uses the following cookies:

- `.EPiForm_VisitorIdentifier` – Functionality-related. Identifies the form submission to the site when a visitor submits data through an Optimizely form. Stores a GUID, which is the visitor identifier. Persistent (90 days from creation).
- `.EPiForm_BID` – Functionality-related. Identifies the form submission made to the site when a visitor submits data through an Optimizely form. Stores a GUID as the browser ID. Persistent (90 days from creation).
- `EPiForm_{FormGuid}:{Username}` – Functionality-related. Stores partial form submissions so visitors can continue with a form submission upon return. One cookie is created for each form and visitor who is logged in. Stores the current submission status of the form (`formGuid`, `submissionID`, and if the submission is finalized or not). Persistent (90 days from creation).

:::hint{type="info"}
**Note**
The following are **internal cookies** (implemented by below service classes) and should not be touched. If you really need to, change the class to your implementation.

- `EPiServer.Forms.Core.Internal.ProgressiveSubmitInfoService`
- `EPiServer.Forms.Core.Internal.VisitorIdentify.DefaultVisitorIdentifyProvider`
:::

You can set up a time to expire these cookies by changing the value of `visitorSubmitTimeout` in `Forms.config`. The default is 90 days.

## Protect visitors' privacy

According to EU directives, website owners are responsible for informing visitors about cookies used on the site. See [Protect your visitors' privacy according to EU directive on cookies](https://world.optimizely.com/articles/Items/Protecting-Your-Visitors-Privacy-According-to-EU-Directive-on-Cookies/).