Even if your retirement is years away, it's a good idea to periodically check in on your Social Security benefits.
(Checking in is getting an extra layer of security. Earlier this month, the Social Security Administration announced it will enable two-factor authentication starting June 10, requiring account holders to log in and provide an additional point of identification via cellphone or email.
"Using two ways to identify you when you log on will help better protect your account from unauthorized use and potential identity fraud," the agency said in its announcement.)
Here are three more Social Security surprises to be aware of: