$100 a month in the S&P 500 since 2006

Investing $100 every month in an S&P 500 index fund from January 2006 to Sep 2026 added up to $24,900. With dividends reinvested, it would be worth about $121,342.

Real monthly S&P 500 data, updated monthly. How we calculate
Start
End

What most index funds and dividend reinvestment plans do.

$100 a month into the S&P 500 since Jan 2006 is worth

$121,342

You would have put in $24,900 over 249 monthly buys. At the worst point, around Nov 2008, the balance was down 22% from its high, and the plan kept buying.

$24,900You put in
+$96,442Growth
13.5%Per year
−22%Worst dip
$0$50k$100k$150kJan 2006Sep 2008May 2011Jan 2014Sep 2016May 2019Jan 2022Sep 2024Sep 2026
Value (S&P 500)Money you put in

If you had invested the whole $24,900 in Jan 2006, it would be worth $218,175. S&P 500 monthly average prices, dividends reinvested (recent months use the last reported dividend, Jun 2023). Data through Sep 2026. One buy per month at that month's average price; no fees or taxes. Past returns do not predict future returns.

The result

$24,900You put in
$121,342Worth in Sep 2026
13.5%Yearly return
−22%Worst drop on the way

That is 249 monthly buys. The balance ended at 4.9× the money put in, a money-weighted return of 13.5% a year. Without reinvesting dividends it would be $96,094, so dividends added $25,248.

Prices rose along the way, so the deposits are worth more in today's money than their face value: $24,900 of deposits equals about $33,832 in today's dollars. Even measured that way, the plan ended 3.6× ahead.

The hardest stretch: the balance fell 22% from its high around Nov 2008, during the 2008 financial crisis. Someone who kept buying through that drop bought shares cheaply, which is a large part of the final number.

How the balance grew
AfterPut inWorth
5 years (2010)$6,000$6,647
10 years (2015)$12,000$20,310
20 years (2025)$24,000$106,804
Now (Sep 2026)$24,900$121,342

How the balance grew, with dividends reinvested. No fees or taxes.

Try other amounts and years

Common questions

How much is $100 a month in the S&P 500 since 2006 worth today?

About $121,342 as of Sep 2026, from $24,900 invested, with dividends reinvested and no fees or taxes.

What was the yearly return?

13.5% a year, measured as a money-weighted return that accounts for when each monthly deposit went in.

What was the worst moment?

A 22% fall from the previous high around Nov 2008, during the 2008 financial crisis. The plan only reached today's value because the buying continued.

Will the next 21 years be the same?

Nobody knows. Past returns do not predict future returns, and the S&P 500 has had decade-long stretches with little gain.

Based on the S&P 500 monthly average level with dividends reinvested (an index fund before its small fee). Educational estimates, not investment advice. Past returns do not predict future returns.

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