Confirmation Page
Confirmation Page

Definition
A confirmation page is the first page a visitor sees after a conversion and normally will provide details of the order, including the price and delivery time scales. It is also a great time to request something else as customers have just made a commitment to a purchase. They may be willing to celebrate through social sharing and will be most open to other requests as they seek to reassure themselves they have made a good decision.
This means it can be a good time to also ask for personal details to improve your customer profiling. Recommend a related product or seek a further conversion. Many organisations also use this opportunity to capture Voice of Customer feedback. Visitors are usually in a positive frame of mind after completing a task.

Source: Amazon.co.uk
This confirmation page from Amazon uses the opportunity to promote items related to the purchased product. It also displays personalised recommendations that are linked to the conversion.
Confirmation pages are also where enhanced ecommerce tracking using Google Tag Manager or another tag management platform is implemented. By implementing enhanced ecommerce on the purchase confirmation page you can capture ecommerce data. Such as transaction ID, revenue, tax and product details. This data is sent to the data layer so that GTM can then send it to your Google Analytics property for analysis and inclusion in ecommerce reports.
On many sites the confirmation page is part of a single page application. This means the URL does not change when a new page is served to the user and so GTM won’t fire a new page view. To track a SPA in GTM you will either have to use either a virtual page view, a URL fragment or an element visibility trigger.
Resources:
Enhanced ecommerce – How to set up enhanced ecommerce with Google Tag Manager.
A/B testing software – Which A/B testing tools should you choose?
Types of A/B tests – How to optimise your website’s performance using A/B testing.