Amazon EC2 Reserved Instances and Other AWS Service Reservation Models
AWS Whitepaper

Amazon Redshift Reserved Nodes

In AWS, the charges that you accrue for using Amazon Redshift are based on compute nodes. Each compute node is billed at an hourly rate. The hourly rate varies depending on factors such as AWS Region, node type, and whether the node receives on-demand node pricing or reserved node pricing.

If you intend to keep an Amazon Redshift cluster running continuously for a prolonged period, you should consider purchasing reserved-node offerings. These offerings provide significant savings over on-demand pricing. However, they require you to reserve compute nodes and commit to paying for those nodes for either a one-year or a three-year duration.

For more information about Amazon Redshift reserved node pricing, see Reserved Instance Pricing and Purchasing Amazon Redshift Reserved Nodes.