another link
Social Security Spouse Benefit – Called A Social Security Spousal Benefit
in your particular example, basically if you are both full retirement age and both entitled to 2500 on your own records:
1) you are entitled to 2500 on your own record
2) you are entitled to half of his , 1250, as a spousal benefit
3) what you get is the larger of the two which equals 2500
Another example, same age assumptions. H is entitled to2500, W is entitled to 1000 , both on own records.
1) you are entitled to 1000 on your own record
2) you are entitled to half of his, 1250, as a spousal benefit
3) what you get is the larger of the two which equals 1250 (tho technically perhaps you are considered to be getting 1000, your own, plus 250, the difference between the 2.
There are other details if you are not the same or full retirement age that might affect the numbers.