If you decide to invest it (in an index fund, for example SPY or IWM), I am not seeing any downside to selling cash secured puts. For example, on SPY, you could sell a short 48-dte 30-delta put (strike $312 on Sept 18) for $616 premium. If it is assigned (SPY goes below $312 on Sept 18), you will get 100 shares of SPY for $31,200 but you are no worse off than if you had bought today and also you will have reduced your cost basis to $30,584. If SPY goes up, the shares will not be assigned; pocket the $616 premium and repeat the cycle. Repeat this loop until your entire $450k is invested. This also has the advantage of spreading out your purchases, and thus dollar cost averaging them. Just a thought... I welcome any criticism of this approach :-)