One of the main reasons why this is needed is so they can continue their shopping experience on another device. Oftentimes, they’ll shop on mobile and purchase on desktop. See best practice #90 for more details on that.
Another reason why users save their cart for later is to make sure they won’t lose the items in their cart, thus allowing them to continue shopping at a later time. Lots of stores don’t have a persistent cart.
So that brings us to the importance of having a persistent cart on your store (see best practice #106). That will simplify things for users who want to keep their cart, not having to save it for later.
Most of the big brands I looked at do allow users to save individual cart items for later. Some of those stores require users to log in in order to do so. Others have a persistent cart. And some have neither a forced login or a persistent cart, which means that when users come back the next day, their cart is empty and they’ve lost what they wanted to save (if the user didn’t log in).
None of those brands offer the possibility to save the whole cart for later.
My recommendation here is:
- Have a persistent cart (see best practice #106)
- Encourage (but don’t force) users to log in / register when they save a cart item for later
- Add a button to save the whole cart for later, which then gives the option to send themselves an email with a link to their cart contents, or login/register.