When adjusting for payroll taxes against all government benefits received, illegal immigration creates an annual deficit of around $55 - 115 billion dollars depending on the source study used. That's the price tag for cheap strawberries and it doesn't include the $100+ billion dollars in remittances sent back home to origin countries. Amnesty also provides zero relief. If all current illegals were granted amnesty, the long term lifetime impact would be roughly $6.3 trillion in deficits. Source: google search function

Yes - they pay taxes, but the net net to America is a great big ol' hole in the pocket.