This article explains how to install a Google Customer Reviews module.

The Google Customer Reviews module works using an opt-in entry. There will be one proposal per customer to participate in the Google Customer Reviews program. When a customer signs up, they receive a one-time email from Google to write a review about your business after they make a purchase. Check out the Google Customer Reviews Surveys for more information.

Google will feature the reviews in the optional Google Customer Reviews badge, in the Google Merchant Center dashboard, and as seller ratings (stars/reviews on Google Shopping and ads).

Seller Rating: Green stars on your Google Shopping:

Seller Rating: Stars on your default ads:

Reviews when you click on the stars/rating:

Requirements

To use Google Customer Reviews:

You must have a Google Merchant Center account.

To make your Google Customer Reviews visible, you'll need:

At least 150 reviews within 12 months
An average of 3.5 stars or higher

Instructions

Activate Google Customer Reviews in Google Merchant here.
Confirm the terms and agreements.

Copy the code snippet:

<script src="https://apis.google.com/js/platform.js?onload=renderOptIn" async defer></script><script>window.renderOptIn = function() {window.gapi.load('surveyoptin', function() {window.gapi.surveyoptin.render({// REQUIRED FIELDS"merchant_id": XXXXXXXXX,"order_id": "#{{ order.information.number }}","email": "#{{ order.customer.email }}","delivery_country": "#{{ order.shipping.country_code }}","estimated_delivery_date": "#{{ order.date_raw | date_modify("+1 day") | date('Y-m-d') }}","products": [{% for product in order.products %}{"gtin":"{[ product.ean }}"}{% if not loop.last %}, {% endif %}{% endfor %}]});});}</script></script>

In your eCom Back Office, click on Settings > Web Extras.
Scroll down to the FOLLOW section and paste the code snippet.
Replace XXXXXXXX with your merchant ID, which can be found in the top right corner of the Google Merchant Center screen.
Look for the estimated delivery date in the snippet and change the expected delivery date to the average delivery frame. +1 means delivered tomorrow.
Click on Save.

Optional Badge Integration

You can add a badge to your site to show your favorite review to your customers. However, if no seller ratings are available, the message "no rating available" will appear. See the terms and conditions in this article for more information.

Integrate the Customer Reviews badge at the bottom of your screen, on the left or right side.

Copy this code snippet:

<script src="https://apis.google.com/js/platform.js?onload=renderBadge" async defer></script><script>window.renderBadge = function() {var ratingBadgeContainer = document.createElement("div");document.body.appendChild(ratingBadgeContainer);window.gapi.load('ratingbadge', function() {window.gapi.ratingbadge.render(ratingBadgeContainer, {"merchant_id": XXXXXXXXX, "position": "YYYYYYYYY"});});}</script>

In your eCom Back Office, click on Settings > Web Extras.
Scroll down to the section JAVASCRIPT and paste the code snippet.
Change the merchant_id (XXXXXXXXX) to your own code. These can be found in the original code snippet added in the FOLLOWING' section.
Change the position (YYYYYYYYY) to BOTTOM_LEFT or BOTTOM_RIGHT.

You can also integrate the Customer Reviews badge anywhere in your eCom store. This will require you to edit your theme's code. Editing your theme's code has certain consequences, as explained here.

Copy and paste the code at the bottom of your theme's code in the place of your choice.
Change the merchant_id (XXXXXXXXX) to your own code.

<script src = "https://apis.google.com/js/platform.js?onload=renderBadge" async defer> </script> <g: rating badge merchant_id = xxxxxxx> </ g: rating badge>