State Street's SPYM and Vanguard's VOO now provide nearly identical S&P 500 exposure, so their one-basis-point fee difference is real but unlikely to be decisive for most long-term investors. State Street lists SPYM's gross expense ratio at 0.02%, while Vanguard lists VOO at 0.03%. On a $100,000 position, that gap is about $10 a year before trading costs and tracking differences.
The more important comparison issue is historical consistency. State Street discloses that SPYM followed several large-cap benchmarks before adopting the S&P 500 in January 2020. Its long-term performance series therefore links periods governed by different index methodologies. That is standard and disclosed, but investors should not read the entire since-inception record as if the fund always held today's S&P 500 portfolio.
For current exposure, both funds track the same capitalization-weighted index and consequently share its concentration in the largest technology companies. Liquidity, bid-ask spreads, tax circumstances and the platform where an investor already holds assets may matter more than a one-basis-point expense advantage.
SPYM is the cheaper fund on its stated fee. VOO offers a longer uninterrupted S&P 500 tracking history. The practical choice should rest on current tracking quality and total ownership cost, not a superficial comparison of linked long-term returns.