I'm 47 and planning $0 from SS. Anything I get will be gravy.
In some ways, of course, that is the ideal approach.
However, for this with not as long a time horizon this assumption could mean needless years of scrimping and saving and working.
I was running numbers in the Firecalc last night. I am 55 and my husband 62. I was playing around with retirement 5 years from now. If I plug in our existing 401(k)s, taking DH's pension as a lump sum in 5 years and combined social security income of roughly $50k, the firecalc says we have a 100% chance of not running out of money even if we never save another penny.
OK, run the calculator again but take out the social security...not so good.
So I added in savings over the next 5 years. Even saving as much as $75,000 a year didn't do it.
To get to a 99% chance of success I had to put in saving $75000 over the next 7 years, delaying my husband's retirement to age 71 or alternatively him retiring and me continuing to work (the most likely possibility).
So assuming that we will get zero from social security would mean that we needed to save $75,000 a year for the next 9 years. Assuming social security will exist, we could both retire in 5 years (if we chose) and wouldn't have to save a penny during that 5 years.
I have to say that neither assumption really makes me happy. It just seems nonsensical for us to assume at our ages that Social Security will just totally vanish. And, making that assumption could mean years of scrimping and saving every extra penny and years of extra work.
On the other hand, I do think we should allow for some uncertainty. While Firecalc says we would be fine without further savings I am mindful that expenses could be greater than I project, etc. So we do plan to save over the next 5 years. An average of $60k a year (maxing out 401(ks) plus a bit more) is probably doable, even a bit more. And, of course, I probably will continue working somewhat longer.
What I find difficult to determine is what to chose to model this for planning. I want to count something for Social Security but counting all or nothing seems unsatisfactory.