Taxes And Compounding (Dividend Taxes)
Last Updated on December 22, 2020 by Oddmund Groette

To shelter your savings from taxation while building your nest egg is extremely important. I believe this is pretty obvious for most investors, but I suspect it’s still neglected because the headwind takes about ten years to really make a difference. Having a tax-deferred account is essential for letting your capital compound efficiently.
Unless you have a tax-sheltered account you will take a beating whenever you receive a dividend or sell a profitable position. Most countries offer some form of tax-sheltered accounts and you should use them to your full benefit.
An example: compounding – with and without taxes
The graph below illustrates a 50 000 account compounding at 9% for 40 years:

The blue line is 9% compounded for 40 years without taxes, while the pink line subtracts 25% taxes on unrealized gains every year. By delaying taxes you more than double your wealth. Quite a difference!
Obviously, the tax-scenario is a bit unrealistic because unrealized capital gains are not taxed, so let’s change the circumstances a bit:
Let’s assume you own shares in Microsoft worth 25 000 with a cost price of only 5 000. You have turned bearish on Microsoft and would like to switch to Berkshire shares, but unfortunately, the shares are in a taxable account. You estimate Microsoft can only compound at 8% over the next decade, while Berkshire’s can compound at 12%. A switch to Microsoft needs to take into consideration the effect of the tax rate of 30%. If you sell Microsoft, you will only have 19 000 to reinvest because of 6 000 in taxes (20 000 x 30%). If your future estimated returns are correct, the alternatives are like this:
Value today | Value in 10 years | CAGR | |
Microsoft | 25 000 | 54 000 | 8% |
Berkshire | 19 000 | 59 000 | 12% |
This means you are better off switching to Berkshire instead of Microsoft. The alternatives are equal if Microsoft compounds at 9%. In other words, the tax equals a 3% annual “penalty” over a ten-year period.
Taxes on dividends
Taxable dividends face the same challenge. The graph below shows 1 000 shares in VNQ purchased in early 2005 (56 750 USD) and held until September 2019:

The blue line is reinvested dividends without taxes while the pink line is the same dividend less 20% taxes. A no-tax scenario compounds the value to 182 000 USD, while only 159 000 subtracted 20% taxes. The difference in CAGR is 8.07% versus 7.12%.
Conclusion:
You face some serious headwind if you keep your stocks in a taxable account, and the drag compounds over long time-horizons. A 1% annual difference amounts to a much smaller nest egg for your retirement.