How can I invest in single US Stocks using CPF OA?

Sorry mate, as the joke goes "70% vote for it"

On a serious note, cpf is meant for retirement purposes, so im highly doubtful that gov would allowed money to flow out of our shores into the "volatile" overseas market, away from supervision. cpf monies only allowed for sgx stocks, providing a much need ancillary liquidity to a lacklustre domestic stock market

You can only invest in (individual) stocks listed on SGX (full list here). If you would like to invest CPF-OA and gain exposure to US markets, you can consider Endowus.

Full list of investment products available can be found here: https://www.cpf.gov.sg/Assets/members/Documents...