Amazon SQS does not charge for queue existence, message storage, or the number of queues — cost is driven entirely by API requests and data transfer. When consumers continue polling a queue that no longer receives messages, every ReceiveMessage call that returns empty is billed at the same rate as a call that returns data. These "empty receives" are the most common source of unexpected SQS charges and represent pure waste when the queue serves no active purpose.

This pattern is especially prevalent in serverless architectures where Lambda functions are configured as SQS event sources. In this setup, AWS automatically manages a fleet of pollers that continuously make ReceiveMessage calls to the queue — starting with multiple concurrent pollers and scaling based on message volume. Even on a completely idle queue, this automated polling generates a steady stream of empty receives around the clock. Because the polling is managed by the platform rather than application code, teams often overlook it entirely.

While the cost per individual idle queue may appear modest, the waste compounds quickly across organizations with many queues spanning development, staging, and production environments. The SQS free tier can mask the issue in small deployments, but organizations with dozens or hundreds of forgotten queues — each with active consumers or Lambda triggers — can accumulate meaningful unnecessary spend.