How much TCS pay for onsite ?

I get two different project offer from my internal contacts. By the way I am not on bench but can get release from my current project and onboard the other. Two different projects, one is in UK and other is in USA. How much tcs offers to C3A band resource for both the onsites per month ? I have a kid and wife is housewife. How much I can save per month in terms of Dollar or Pound per month considering basic life style ?