How-to Guide: Trustpilot's Unique Link invitations

Would you like to manage your entire invitation-to-review process using your in-house tools? Then the Unique Link might be the right feature for you.

Get a Unique Link overview here - What it is, how it works, and how to generate the link. This article is intended for developers.

Please note: The technology used to protect personal information in the Unique Link is now considered outdated, so Trustpilot recommends using the Business Generated Link instead. The Business Generated Link protects your customers' personal information using advanced 256-bit AES encryption.

What is a Unique Link?

A Unique Link is an invitation link for consumers to post service reviews - without having to log in. Each of these links is unique to specific customer-company interactions. Creating a Unique Link allows your company to manage the entire invitation-to-review process using your in-house tools. The Unique Link is generated and stored on your company’s server, this is useful when sharing customer information with Trustpilot is not an option.

How does it work?

The Unique Link consists of the information a customer requires to be able to write a service review, i.e. a name, a reference number, and an email. All three elements are contained inside the URL, so this information won’t be shared with Trustpilot until the link is clicked. To make sure the link comes from your business and not a third party, the link also includes a hash containing the information and a Unique Link Secret Key made by Trustpilot for you.

Here’s an example of a Unique Link using the following information:

  • Domain Name:
  • Reference Number: A1B2C3
  • Customer Email:
  • Customer Name: John Smith
  • Unique Link Secret Key: TrustpilotSecret

Note: You will receive the Unique Link Secret Key from your Account Manager at Trustpilot.

The Unique Link will look something like this:{BASE64(}&c={encodeURI(John Smith)}&e={SHA1(TrustpilotSecretjohn@example.comA1B2C3)}

The braces {} indicate that the information contained within must be hashed/encoded. The hash/encoding format is defined in the braces; the formats are either BASE64, SHA1, or encodeURI. You will need to have a programming language that supports these formats, or use compatible third party implementations. The parentheses () contain the information which is to be hashed/encoded.

Generating a Unique Link

If you want to test it, the link can be generated in real time here:

Note: This program is ONLY for testing. To use the Unique Link in a production environment, you should program it to work dynamically with customer data.

If the URL was created correctly, it should look like the left image. If there is an error in the URL, it will look like the image on the right:

A correctly functioning Unique Link will allow the recipient to leave a review without having to log in.

Having issues with the &e= parameter (SHA1 hash)?

SHA1 only takes a single parameter which is the concatenated string of the 3 required values. Please ensure they are in the exact outlined order.

The most commonly reported issue with the Unique Link is that the hash is incorrect. In order to illustrate exactly how the hash should be made and what it should look like, we have made a testing tool for this as well: