Daily Cognito Audit Job Could Silently Inflate AWS MAU Billing

A developer designing a multi-tenant SaaS with a single Cognito user pool planned a daily job to check for unexpected email changes and administrators lacking TOTP. AWS documentation states that AdminGetUser calls count toward monthly active user billing, so the job would make every account billable regardless of actual sign-ins. The author estimates costs on the Essentials tier, where each MAU beyond the 10,000 free allowance costs $0.015, and notes the cost scales with signed customers rather than usage. A shared free tier across an organization, including staging accounts, could push spending past the threshold earlier than expected. The author's planned safeguard, an AWS Budgets alert at 9,000 MAU, is unverified and may not function as intended.