AWS launches hard spend limits, a brake on runaway agent bills

AWS announced project-level monthly spend limits on September 16: when a project's usage reaches its limit, the project is paused for the rest of the month, rather than merely sending a warning email.

The backdrop is that coding agents make it trivially easy to deploy services that keep billing — and people have woken up to runaway services that burned thousands of dollars overnight. Google Cloud launched a similar feature, Spend Caps, in July, letting users cap monthly spend on specific services within a project.

Simon Willison argued in an October 3 blog post that hard caps should be the default, with removal as an explicit opt-in. AWS's own documentation notes the feature is currently releasing to a limited number of customers, with no timeline for existing accounts.