Any index to recommend for S&P 500?

My pick would be CPSX if you have LSE access and IVV if you don't have LSE access. CSPX is overall more cost efficient due to withholding tax differences (15% vs 30% on the US side).

I have covered more on how to choose between S&P 500 ETFs in my article here!

US domiciled and listed (30% withholding tax):

• SPY (State Street, TER 0.095%)

• VOO (Vanguard, TER 0.03%)

• IVV - (iShares, TER 0.03%)

Irish domiciled, LSE listed (15% withholding tax):

• CSPX (iShares, Accumulating, TER 0.07%)

• IDUS (iShares, Distributing, TER 0.07%)

• VUAA (Vanguard, Accumulating, TER 0.07%)

• VUSD (Vanguard, Accumulating, TER 0.07%)

• SPY5 (State Street, Distributing, TER 0.09%)

• SPXS (Invesco, Accumulating, TER 0.05%)

• SPXD (Invesco, Distributing, TER 0.05%)