We can enable billing access to an IAM user account. The access is disabled by default on all aws accounts.
First need to Activate IAM Access from the My Account > IAM user access to Billing information, when you are logged in as root. https://console.aws.amazon.com/billing/home?#/account
If you do not do the above step, even if your IAM account is into the Admin group, you won’t have access to billing section. It will be still throwing the error as below.
The AWS link below describes on how to setup access for an IAM user.
http://docs.aws.amazon.com/awsaccountbilling/latest/aboutv2/billing-permissions-ref.html
You can attach the below policy to the user from the Users section to provide view only access. Better still, you can use the policy generator to give you the access that you require.
{ "Version": "2012-10-17", "Statement": [ { "Sid": "Stmt1453424203000", "Effect": "Allow", "Action": [ "aws-portal:ViewAccount", "aws-portal:ViewBilling", "aws-portal:ViewPaymentMethods", "aws-portal:ViewUsage" ], "Resource": [ "*" ] } ] }