The Treasury Department began mailing checks for the advance payment of the increased Child Tax Credit on July 25, with most checks mailed by August 8. These covered eligible taxpayers who filed their 2002 tax returns by April 15, 2003. As the IRS processes returns from taxpayers who filed after that date, it will schedule advance payments on a weekly basis. No checks will be sent after December. For the first three weeks, the checks were sent according to the last two digits of the taxpayer's social security number: 00-33 -- mailed July 25 34-66 -- mailed August 1 67-99 -- mailed August 8 Eligible taxpayers whose returns were not processed in time for these initial mailing dates will have their checks sent out after the IRS processes their returns.