I note that the Hargreaves Lansdown website (not an endorsement in any way - there are others I'm sure) lists quite a few, but not all of the Vanguard ETFs, with a US ISIN number and US domicile, and I believe that these would be considered NOT PFICS. The question then is how to match them to the HMRC list of Reporting Funds. As an example, the Vanguard Index Trust Stock Market Vipers (VTI) is listed on the Hargreaves Lansdown site as having a US domicile and an ISIN number of US9229087690, and the ticker is VTI. This fund is similarly listed on US sites under this ISIN no., but generally under the title Vanguard Total Stock Market Index Fund - ETF Shares.
HMRC lists ths fund as Vanguard Total Stock Market Index Fund - ETF Shares, similar to US sites, but it does not give an ISIN number or ticker. But it does give the CUSIP number as 922908769, i.e. the same as the ISIN number but without the US domicile identifier and the trailing zero which I believe is there for padding rather then for any identification purpose. it seems to me therefroe that both these listings refer to the same fund, and it is therefore a reporting fund that is not a PFIC, and so safe for both US and UK taxpayers to invest in without problems.
I would not say this if it had an ISIN number on the HMRC website beginning with IE which indicates Irish domicile - then it would be a PFIC I think.
In all I have identified 46 Vanguard Funds that satisfy both criteria on the HL website - this may change of course.
I would welcome a second opinion on this - I'm not a professional so my research is open to review and correction - and it would help me and others solve what seems to be a common roblem.
Thanks, PL