Data Transfer within the same AWS Region
Data transferred "in" to and "out" from Amazon EC2, Amazon RDS, Amazon Redshift, Amazon DynamoDB Accelerator (DAX), and Amazon ElastiCache instances, Elastic Network Interfaces or VPC Peering connections across Availability Zones in the same AWS Region is charged at $0.01/GB in each direction.
Wrong. Depends on the use case AWS can be very cheap.
> splitting amongst AZ's is of no additional cost.
Wrong.
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across Availability Zones in the same AWS Region is charged at $0.01/GB in each direction. Effectively, cross-AZ data transfer in AWS costs 2ยข per gigabyte and each gigabyte transferred counts as 2GB on the bill: once for sending and once for receiving."