I guess my point is these outrageous marginal tax rates apply in few cases and to relatively narrow bands of income so while they are important to know about for decision analysis (what is the tax if I do an additional $2k of STCG or Roth conversion) they do not apply so broadly as to be cruicial to retirement tax planning generally.
A simple takeaway here is that when people are thinking of doing Roth conversions in the years before taking SS, the future tax rate may be higher than it seems. If it looks like you have the same tax rate now and in retirement, do conversions now, because it's likely that at least some of your RMD income will cause a higher marginal tax rate than you think. To see if it actually applies takes more work: see if it would push more SS into being taxed at 85%, and also if any LTCGs/QDivs would be pushed into being taxed at 15%. Also see if the extra SS taxable income pushed you into the next tax bracket.
There is a 40.7% marginal tax rate that starts when you enter the 22% federal tax bracket and ends when 85% of your Social Security has been taxed. 185% of 22% is 40.7%.
The average yearly SSB in 2017 was only $16,320. At benefits levels that low the 85% already taxed point is reach before the 22% bracket so this large marginal bracket does not exist for most of us.
If you wait until age 70 to start your benefits, your benefits will be somewhere between $20,000 to more than $40,000. Here are the statistics for single individuals on the size of the 40.7% bracket at those SSB levels:
SSB + Other Income – Fed Tax = After Fed Tax Income
$20,000 + $36,865 - $4,453 = $52,412, next $1,841 at 40.7%
$30,000 + $34,568 - $4,453 = $60,115, next $9,138 at 40.7%
$40,000 + $32,270 - $4,453 = $67,817, next $16,436 at 40.7%
You said that these rates only apply in a few cases, but there is one segment of the population where they probably apply in the majority of cases, surviving spouses!
Shirley is a widow. We did a lot of pre-planning. She retired early and started her survivor benefits before the age of 62 and will wait until she is 70 to start her own benefits. This will place her in the category of facing the 40.7% marginal rate for a substantial portion of her future income. For her and most other surviving spouses this is not a “narrow band of income”.
Let me repeat something I said in an earlier post. “If you are getting $40,000 in SSB and $32,270 from pensions, annuities, and IRA withdrawals, the basis for the taxation of your SSB is $52,270 which makes $20,030 of your benefits taxable, a fraction over 50%, the other 50% will be tax free. Your overall Federal tax rate is only 6.16%. If this is your situation, do you want to pay 40.7% on the next $16,436 of income while the other half of your SSB is taxed?”
One interesting point here is that, regardless of your SSB level, the taxes paid at the point where you enter the 22% Federal bracket, 40.7% marginal, is:
Tax rate | Single | Tax |
10% | Up to $9,525 | $952.50 |
12% | $9,526 to $38,700 | $3,501 |
| | $4,453.50 |
If some of your extra $32,270 income is from LTCGs, they are tax deferred, so your taxes paid will be less, but the 40.7% bracket will start at the 49.95% level as your LTCGs become taxable.
Since the research that I am doing is designed for Widows and Widowers, I should probably preface most of my posts with a statement that they are meant for surviving spouses.