Missouri is one of the few states that taxes some of your Social Security benefits. You do need to have gross income of $85k for single taxpayers and $100k for Married Filing Jointly before your benefits are taxed.
However, ALL of your retirement income is taxed, IRAs, 401ks,, 403bs, TSPs and 457s. Now some pension income has some exemptions but you really need to have low income to qualify. Military pensions are tax-free, be advised.
So, in Missouri, just assume all of your retirement income is taxed. And once you break $9k of TAXABLE INCOME your tax rate is 6%.
State sales tax of 4.225% seems low. But when you factor in local taxes, the sales in Missouri almost double what the state tax rate is. In fact, the total sales tax in Missouri puts them in the top 15 for highest in the nation.
Lastly, property taxes are 1.02% of assessed value. Unless your income is very low there is no homestead exemption either.
So, by and large, Missouri isn’t a tax Heaven or a tax Hell. It’s smack in the middle of the US for overall tax rates for retirees.