**by Nidin Shah


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This report documents a real billing incident on my personal AWS account. It covers how I discovered unexpected charges, investigated the root cause, and what I learned about AWS cost management as a beginner.

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Overview

As someone new to AWS, I started exploring cloud services through personal lab projects involving EC2, Load Balancers, and networking configurations. During this process, I accidentally incurred unexpected charges because some resources were left running after I finished testing. This experience gave me hands-on exposure to how AWS billing works, how to use Cost Explorer and AWS Budgets, and why resource cleanup is a critical habit not just a good-to-have.

Field Detail
Account Personal AWS Free Tier
Month-to-date cost (at discovery) $6.22
Forecasted monthly cost $19.16
Last month's total $17.58
Budgets exceeded 2 active budgets over threshold
Root cause Amazon Elastic Load Balancing (ELB)
Status ✅ Resolved

Discovering the Charges

While checking my AWS account, I noticed my billing amount was increasing even though I had already completed my lab testing.

I then navigated to:

AWS Console → Billing and Cost Management → Cost Summary

There, I discovered active charges, a forecasted monthly cost of $19.16, and several services still running in the background — including two budgets that had already exceeded their threshold.

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Investigation — What I Actually Went Through

This is where I made the most mistakes, and learned the most.

[Toggle block — "Week-by-week breakdown"]

Day 1 — Received a budget alert email from AWS warning that my spending had exceeded the limit I set. I opened the console but wasn't sure where to look first.

Day 2–3 — Went straight to the EC2 dashboard. Found running instances and assumed they were the problem. Stopped all of them.

Day 4–5 — Checked billing again. The forecasted cost was still $19/month. Confused why stopping EC2 didn't fix it. Decided to fully delete the instances.

Day 6 — Still seeing high charges. This time I opened the Cost Breakdown chart and changed "Group costs by" to Service. For the first time, I could see clearly — EC2 charges were small. The biggest bar was Elastic Load Balancing.

Day 7 — Navigated to EC2 → Load Balancers. Found one Application Load Balancer sitting idle — no targets, no traffic — but fully provisioned and charging ~$0.025/hour around the clock. Deleted it. Problem resolved.

Finding the Cause