How much people think they'll get from Social Security in retirement is much more than what they'll probably wind up getting, said CNBC. This is according to a recent survey by the AARP which found that roughly half of consumers aged 45 to 64 believe that Social Security will be a major part of their income once they retire. Financial planning professionals, however, aren't as optimistic. The same survey found that 94 percent of certified financial planners say Social Security will make up less than half of retirement income for their clients, with 53 percent going so far as to say it would only be 30 percent or less. Overestimating how much Social Security money will come in the future can have dire impacts on behavior in the present, according to CNBC, as people will be less likely to save as much, as they think they don't need to. The survey polled 1,200 future Social Security beneficiaries as well as 1,300 financial planners to find where the knowledge gap was in how people think Social Security works and how financial professionals know it works.