I haven't looked into Amazon's finances extensively, but I bet this is at least partly due to Net Operating Loss. In US tax law net operating loss means that yo

I haven't looked into Amazon's finances extensively, but I bet this is at least partly due to Net Operating Loss. In US tax law net operating loss means that you can deduct losses for prior years from this year's earnings. The funny thing about this is that by losing money you actually add an asset to your balance sheet (deferred tax assets). Since Amazon has lost a lot of money in the past that probably helped with their 2017 taxes. Another interesting thing about this is with the new tax law cutting the corporate tax rate to 21%, many companies had to take a charge against earnings in order to write down the value of the deferred tax assets. If you lost $1M last year, you had $350,000 in deferred tax assets that got written down to $210,000 meaning your company technically lost $140,000, even though you got a tax cut. Accounting is truly amazing.