Long-Term S&P 500 Holding or Greater Liquidity? VOO vs. SPY

The Vanguard S&P 500 ETF (VOO) and the SPDR S&P 500 ETF Trust (SPY) both give investors access to the same S&P 500 benchmark. The key difference is not what they own, but whether an investor values lower long-term costs or the deeper liquidity that can matter when trading larger positions.