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/Reserved Instance, then become our billing double./

Reserved Instance, then become our billing double.


Hello there, We recently apply reserved instance no upfront, then the next day our billing shows double EC2 bills, can you clarify this ? 1. On Demand 2. Reserve Instance Same specs.

Please advise

2 Answers
Accepted Answer

There could be a number of things happening here.

  • there could be on-demand usage for part of the day and RI usage once the RIs were purchased, after a couple of days, do you see the on-demand go away?
  • is the RI a Regional or Zonal RI? Zonal RIs are for a specific AZ and Regional RIs are for the entire region. Also, are you sure that the on-demand usage reported is in the same region as the RI?
  • UP Front RI usage will not show up in Cost Explorer unless you are viewing Amortized costs.

If you would like support to investigate your specific issue, you are encouraged to raise a Billing Support Case, in the AWS Console, click on the ? with a circle -> Support Center -> Create Case -> Account and Billing Support. The support folks should be able to investigate your specific account and situation.

answered a month ago
reviewed a month ago
  • +1 to this response. There are multiple variables here, and it's better to submit a support case to ask for additional review and investigation. If the attributes of the RI and the running instance match, then the discount should be applying. The most important point is that the billing works hourly. Each hour the system will check if you have RIs and if you have any running instances that match the attributes of the RI, and will apply the discount accordingly. If you purchased the RI mid-month, then any usage BEFORE the purchase, would be stil charged on-demand fees.


Hi There, Thank you for your respond. I have managed this issue with local support and understanding better on our billing now. Thank you

answered a month ago

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