01 December 2015

Lowering your AWS bill by moving to reserved instances

The cost saving from reserving an EC2 instance is quite dramatic.  This morning I moved two web servers to reserved instances and am dropping my hosting cost by 64% for those servers.

There isn't actually any effort required in moving your on demand EC2 instance to a reserved instance.  The only actual change is a billing change, you don't need to do anything in your instance configuration.

The only important thing to remember is that you're reserving an instance in a particular availability zone.  The billing effect will only apply to instances launched in the same availability zone.

Amazon will apply the discount of having a reserved instance to your invoice automatically.  They provide quite extensive documentation on reserved instances on their site (here).
Tip