TSP C Fund vs S Fund

The C Fund tracks the S&P 500 Index: about 500 of the largest U.S. companies. The S Fund tracks the Dow Jones U.S. Completion Total Stock Market Index: U.S. small and mid-size companies not in the S&P 500. From 2004 through 2025, the C Fund averaged 10.72% a year and the S Fund 9.94%, and the C Fund came out ahead in 14 of 22 years.

Side by side

C FundS Fund
Compound average (2004–2025)10.72%9.94%
Best year+32.45% (2013)+38.35% (2013)
Worst year-36.99% (2008)-38.32% (2008)
Years with a loss3 of 225 of 22
2026 so far+11.32%+12.32%

C Fund

The C Fund holds the stocks in the S&P 500, weighted by company size, so the biggest U.S. companies (large technology firms especially) drive most of its daily move.

Risk: Stock fund: higher long-term growth potential than the G or F Funds, with larger ups and downs, including losses.

C Fund details

S Fund

The S Fund holds U.S. stocks that are not in the S&P 500, mostly small and mid-size companies. Together, the C and S Funds cover nearly the whole U.S. stock market. As of December 31, 2025, the latest date tsp.gov shows, its largest sectors were industrials (19.1%), information technology (18.3%), financials (16.3%) and health care (14.2%), and its largest holdings included Snowflake, Marvell Technology, Cloudflare and Vertiv. It holds most of the index's companies worth more than $1 billion and uses sampling for the smaller ones. Its total expense ratio was 0.051%, or $0.51 per $1,000 invested.

Risk: Stock fund: typically more volatile than the C Fund, with larger daily swings in both directions.

S Fund details

Returns by year

YearC FundS FundDifference
2025+17.85%+11.38%+6.47%
2024+24.96%+16.93%+8.03%
2023+26.25%+25.30%+0.95%
2022-18.13%-26.26%+8.13%
2021+28.68%+12.45%+16.23%
2020+18.31%+31.85%-13.55%
2019+31.45%+27.97%+3.49%
2018-4.41%-9.26%+4.85%
2017+21.82%+18.22%+3.60%
2016+12.01%+16.35%-4.34%
2015+1.46%-2.92%+4.38%
2014+13.78%+7.80%+5.98%
2013+32.45%+38.35%-5.90%
2012+16.07%+18.57%-2.50%
2011+2.11%-3.38%+5.50%
2010+15.06%+29.06%-14.00%
2009+26.68%+34.85%-8.17%
2008-36.99%-38.32%+1.33%
2007+5.54%+5.49%+0.05%
2006+15.79%+15.30%+0.49%
2005+4.96%+10.45%-5.50%
2004+10.82%+18.03%-7.21%

Common questions

What's the difference between the TSP C Fund and S Fund?

The C Fund tracks the S&P 500 Index: about 500 of the largest U.S. companies. The S Fund tracks the Dow Jones U.S. Completion Total Stock Market Index: U.S. small and mid-size companies not in the S&P 500.

Which has returned more, the C Fund or the S Fund?

From 2004 through 2025, the C Fund's compound average was 10.72% a year and the S Fund's 9.94%. The C Fund came out ahead in 14 of 22 calendar years. Past performance does not predict future returns.

See every fund's returns by year, or get the free morning briefing on what moved each fund.

Source: official TSP share prices (tsp.gov), through Monday, November 9, 2026. Past performance does not guarantee future results. Educational information, not investment advice; which funds to use is your decision.

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