Spousal benefits are calculated by subtracting your monthly benefit at full retirement age(FRA) from 1/2 of the full retirement benefit of your spouse. If you claim only your benefit early the benefit on your record will be permanently reduced. If you then claim a spousal benefit at 66 the spousal benefit will not be reduced and it will be added to your reduced benefit. As a result, the amount you receive will be higher than if you had claimed both at the same time but below 50% of the benefit. For example, lets say your monthly benefit at FRA is $1000 and your spouses FRA benefit is $2400. Your spousal benefit would be $200(2400/2=1200-1000=200). If you claim your benefit at 62 it would be reduced by 25% to $750. When you claim the spousal benefit at FRA you will receive the extra $200 for a total of $950.