People who aren’t required to file a U.S. tax return have less than three months to alert the Internal Revenue Service if they haven’t yet received a $1,200 stimulus payment from the government, Commissioner Chuck Rettig said Tuesday.

Rettig’s agency is urging those who may be eligible for payments to enter their information on its website by Oct. 15. The IRS is trying to reach out to people who are homeless or otherwise marginalized to get money to them, he said.

“There are tremendous populations in this country who operate outside of any interaction whatsoever with the government,” Rettig said at an IRS forum on Tuesday. “The under-served communities here need help.”

Congress in March approved $1,200 payments for adults earning up to $75,000 and $500 for their children. The payments are phased out for individuals earning up to $99,000 or twice that for a couple. The IRS so far has sent about 160 million payments worth approximately $270 billion, Rettig said.

Senate Majority Leader Mitch McConnell said Tuesday that a new Republican stimulus plan that could be released as soon as this week will include another round of targeted direct payments to individuals. Democrats have also backed a second round of checks. Congress is expected to pass another coronavirus relief bill by early August.