Amazon allows users of Mechanical Turk to set up Amazon Web Services Billing. If you use AWS Billing, you will be issued a monthly invoice for the studies you run on MTurk instead of having to purchase pre-paid HITs.
If you use CloudResearch to conduct MTurk surveys, then you created an AWS account and linked it to your MTurk requester account while taking the steps to set up your CloudResearch account. If you are certain you do not have an AWS account or you are new to CloudResearch, you can find information for creating and linking accounts here.
Once your AWS account is linked to your MTurk requester account, turning on AWS Billing is easy. From your MTurk account page, you can see the AWS Billing option in the header menu. Clicking this option will display the page below with the option to enable AWS Billing. Importantly, once you opt into AWS Billing, you cannot revert back to pre-paying for HITs.
NOTE: When you turn AWS Billing on, Amazon will examine your account and assign you a spending limit. While this assessment is taking place, you may not be able to launch any studies. All questions about spending limits and the review process should be directed to Mechanical Turk.
Once you’ve turned AWS Billing on, you should update your account settings on CloudResearch. By navigating to the account settings page, you will see a new MTurk Billing option. Simply change the billing option from Prepaid HITs to AWS Billing. You will now be able to launch MTurk Toolkit studies without having to prepay for the Amazon portion of your study. Any CloudResearch fees associated with your study will still need to be paid before you can launch the study.