How does a Singaporean (non residential alien) pay for federal income tax withheld for US dividend stocks on my own?

How does a Singaporean (Non residential alien) pay for federal income tax withheld for US dividend stocks? I received a 1042S form from Fidelity Stock Plan Services, a broker that does not assist in filing taxes. I presume I will also need to fill up the 1040NR form. Am I missing anything else? As a Singaporean investor I feel completely lost.

Fidelity will do the filing for you and the withholding tax is already deducted from your dividends when deposited in your account.

The 1042-S form that was sent to you is a copy that Fidelity is required to provide you. On the top right, it should state Copy B to D.

Copy A is sent to the IRS.

https://www.irs.gov/pub/irs-pdf/f1042s.pdf

No action is required from you.

Even for your IRAS tax filing, you do not need to submit any form for your dividends. As dividends from private investments are not taxed by IRAS.

Only exception is any RSUs that have vested in the year which your company will declare to IRAS in your IRA8A. The taxable income will be the price of the stock at grant date x amount of shares vested.