I made purchases thru Amazon. Sometimes they took out tax, and sometimes they did not. How do I know which purchases that did NOT take out sales tax, to include in the use tax calculation? Does Amazon not figure this out for me, meaning I don't need to consider those purchases for the calculation?
Sales tax (if charged) is itemized on your invoice from Amazon. Those purchased items on which CO sales tax was not included would be possibly subject to the use tax. However, certain products and/or services may be exempt from CO sales tax.
The Colorado Use Tax applies when a Colorado resident makes a purchase of goods online, via telephone or via catalog ordering services from an out-of-state seller, and that seller does NOT charge Colorado sales tax on the purchase.
To be compliant, the Colorado resident purchaser must report and pay use tax to the State of Colorado on the purchase.
You will need to review your online, telephone or catalog purchases from out-of-state sellers to verify whether the Colorado sales tax was charged, and if not, pay the sales tax on that item. Any food you purchase is likely not taxable, but clothing, electronics, appliances or other tangible property would be taxable.
For more information, please see the following list of FAQs from the Colorado Department of Revenue, on the Colorado Use Tax:
https://www.colorado.gov/pacific/tax/consumer-use-tax-quick-answers