It is possible to specify the term of how long you will reserve the instance. This can be chosen for 1 or 3 years, the latter being the most economic term. Besides the term, other factors like instance type, size, and availability zone are also used to price the discount. Customers have the option to pay using three options:

• All Upfront (best price)
• Partial Upfront (the discount is proportional to the partial payments)
• No Upfront (pay on a per month basis)

To buy RIs navigate to EC2 | Reserved Instances | Purchase Reserved Instances as shown in the following screenshot:

In the previous reservation, an m5.xlarge is selected with the All Upfront payment option. This search has found four instance options in the N. Virginia region with terms from 12 to 36 months. As you can see in the Offering Class some instances are offered as convertible.