No withholding on pension or social security or part time job. Just sit down four times a year and deal with it. Most years I just do safe harbor (send in a total amount equal to last years total tax liability) regardless what I may owe.
This. We control/vary our income each year with withdrawals, sales, & gifts. So wait till late to withhold.I'm no tax expert, but I rely on the bold.
My pension has typical withholding. I also do "lumpy" distributions from IRAs. I do a rough, estimated tax when I'm getting toward the end of the years, and specify a withholding percent on the last IRA distribution that seems to get me in the ballpark.
I'll consider the 110% safe harbor if it seems relevant in that year.