billing increases suddenly

There are several reasons why you might see increased billing in February even after deleting services earlier in the month:

1. Delayed billing updates: AWS billing systems may take some time to reflect changes in resource usage. Charges from late January or early February could appear later in the month.

2. Residual charges: Some services may have lingering costs that continue until the end of the billing cycle, even after deletion. This can include data transfer fees or storage charges.

3. Overlooked resources: You may have unintentionally left some resources running in other regions or services you don't frequently check.

4. Service dependencies: Some AWS services have dependencies that can continue to incur charges even after the main resource is deleted.

5. Reserved Instances or Savings Plans: If you have any long-term commitments, you may still be charged for these even if the associated resources are deleted.

6. Elastic IP addresses: If you allocated Elastic IPs and didn't release them, they can still generate charges when not associated with running instances.

7. Snapshots and backups: EBS snapshots or database backups may continue to incur storage costs even after the original resources are removed.

To address this issue:

1. Use the AWS Cost Explorer to break down charges by service, usage type, and region.
2. Double-check all AWS regions for any lingering resources.
3. Review your detailed bill in the AWS Billing Dashboard.
4. Set up AWS Budgets or billing alerts to catch unexpected usage early.
5. If you believe there's an error, contact AWS Support for a detailed explanation and potential refund.

Remember, it's crucial to regularly review your AWS account and thoroughly clean up unused resources to avoid unexpected charges.
Sources
Billing forecast information | AWS re:Post
Unexpected EC2 Charges | AWS re:Post
unexpexted Billing | AWS re:Post

Hello.

Specifically, for which services are charges incurred?
Please share an image of your invoice so we can help you find the resource.
Please check your invoice from the URL below.
https://us-east-1.console.aws.amazon.com/billing/home?region=us-east-1#/bills