What is the _sp_id cookie?
_sp_id is an HTTP cookie used by Snowplow, an open-source behavioral data collection (event analytics) platform, often used as an alternative to Google Analytics. The name shown in the browser is usually longer, such as _sp_id.xxxx, where the suffix identifies the collector instance or site.
The cookie is created by the Snowplow JavaScript tracker (snowplow.js or sp.js) on the visitor's first interaction with the page, whether Snowplow runs on the company's own infrastructure or through a third-party provider (self-hosted or cloud-based).
What data it stores
The cookie stores a unique identifier generated for the visitor (domain user ID), along with information about the current session: session number, timestamp of the first and last visit, and the number of page views in the session. The value is typically an alphanumeric string (UUID-like) followed by a few numeric fields separated by dots.
The data is sent to the Snowplow collector configured by the site (which can be a first-party domain, since Snowplow supports first-party data collection) and is used to tie events together into an anonymous or pseudonymous user profile.
What it is used for
The purpose of the cookie is to recognize the same visitor across repeat visits, so the site (or the agency running Snowplow on its behalf) can build reports on traffic, user journeys, conversion rates, and long-term behavior.
Without this cookie, every session would appear as a new visitor, which would significantly distort unique-versus-returning visitor statistics.
Does it require consent?
In CookieFix, _sp_id is classified under the statistics category. Since it is not strictly necessary for the site to function, under the ePrivacy Directive (transposed in Romania via Law 506/2004) and ANSPDCP guidance, setting it requires the visitor's prior consent.
The site administrator should list it in the cookie policy under the statistics category and make sure the Snowplow script does not load before the visitor gives consent.
How to block or delete _sp_id
A visitor can delete or block _sp_id from browser settings (Chrome, Firefox, Safari, Edge – cookies and site data section) or use tracker-blocking extensions.
- Manually deleting cookies for the relevant domain
- Browsing in private/incognito mode
- Anti-tracking extensions or strict browser privacy settings
For site administrators, the correct approach is to technically block the Snowplow script until consent is given. A CMP such as CookieFix can detect the tracking script and keep it blocked automatically until the visitor accepts the statistics category, preventing the cookie from being set prematurely.
Frequently asked questions
No, it is an analytics cookie used for traffic statistics and does not contain sensitive data such as passwords or financial information.
Because Snowplow appends an identifier specific to the collector instance configured by each site after _sp_id, so the full name varies.
The typical duration is around 2 years from the last time it was set, but this can vary depending on each Snowplow implementation's configuration.
Yes, since it is a statistics cookie, GDPR and ePrivacy rules require a consent banner to be shown before it is set.