In an ideal world, it would be simple to prepare to retire single. You would just save half as much as a couple saves, buy half as much insurance coverage, and expect to live on half the income. Reality dictates otherwise.
Although your retirement benefits may be taxed, more retirement income is decidedly better than less – and a key part of retirement planning is estimating both your retirement income need and your retirement income potential.
You know how much retirement money you have. Other factors aren’t as foreseeable. You don’t know exactly how long you will live, so you can’t predict your lifetime Social Security payout. You may even end up returning to work again.