tax on UK dividends payable in US?

I assume that when you state the amount you receive "post-tax" what you mean is the gross amount of the dividend, less applicable UK withholding taxes imposed on the payment of the dividend income to you (as opposed to UK taxes imposed on the company in respect of the company's own income)? If so, then, assuming that the corporation is not a controlled foreign corporation (i.e., generally a corporation of which more than 50% of the company is not owned by persons, each of whom owns 10% or more, and each of whom is a US citizen or resident): 1) As a US resident, dividends received from foreign corporations are included in your gross income. They would be reported on your Sch. B;

2) If the UK tax was withheld from the dividend payment as income payable to you (rather than tax imposed on the company in respect of the company's income), then it should qualify for the foreign tax credit; 3) Alternatively, if it gives you a better tax result, the UK tax can be deducted; however, the foreign tax credit usually gives better results. Lastly, you need to make sure that you're filing all of the other associated forms that cover US persons who own significant interests in foreign corporations. For example, you should determine whether or not you need to file Form 5471. You also need to determine if the company is treated as a Passive Foreign Investment Company ("PFIC"), in which case you will need to file Form 8621. If you haven't filed these forms before you had better make absolutely sure that those forms weren't required for any prior year. The penalties for failure to file can be quite severe.