Social Security benefit may be subject to 1 of 3 potential tax treatments depending on your income at the time you collect:

It won’t be subject to federal income tax.
Up to 50% of it will be subject to federal income tax.
Up to 85% of it will be subject to federal income tax.
Let’s say you retire at age 62 and cover your living expenses by taking withdrawals from a tax-deferred retirement account—a traditional IRA. The amount you withdraw from your traditional IRA will lower your account balance. This may reduce your future required minimum distributions (RMDs), which are calculated by dividing your retirement account balance (as of December 31 of the previous year) by the IRS’s life expectancy factor.

Since your RMD is considered ordinary income, smaller distributions can help you control your income when you begin collecting Social Security at age 70.

if you defer your benefit until you’re age 70 and live until age 90, you’ll collect $652,560 in Social Security over the course of your lifetime. If you don’t defer your benefit and begin collecting at your full retirement age (66), you’ll collect almost $80,000 less over the course of your lifetime.

Lifetime benefit based on age you collect

Note: Example excludes inflation.

The choice is yours

A timeless debate perseveres because it’s a fair fight—both sides of the argument hold water. Folding your pizza makes it easier to eat; not folding it makes it last longer. Cats are independent; dogs are loyal. No matter what you call it, a sandwich is delicious—so just enjoy it. Taking Social Security at full retirement age means you may be able to preserve other financial resources; deferring until age 70 means you’ll get more money when you do collect.

Several personal factors will likely influence when you decide to collect Social Security. At the risk of sounding morbid, you won’t know whether you’ve truly made the “right” decision until it’s too late. So the best advice I have to offer is to choose your Social Security start date based on the facts you know right now. If you get a good night’s sleep after you’ve made your decision, you’re on the right track.

*Source: longevityillustrator.org, supported by the Society of Actuaries.
— Read on vanguardblog.com/2018/05/30/the-social-security-timing-debate/