Ameren officials announced Monday that they'll be sending out $140 million in rebate checks and bill credits starting this week, promising each customer at least $85 back in the mail.

Starting Wednesday, checks will be sent to 935,000 residential customers and continue for a month, closely synched to the company's billing cycle. Credits will show up on bills sent to 133,000 residential customers behind in payments by at least two months and bills for 13,000 small business owners.

Ameren hopes the announcement is the start of a public image turnaround after a year of battering. Customers were caught off guard by huge rate increases in January after a 10-year rate freeze, and the backlash forced Ameren and ComEd to cut back the increases.

"Our customers have asked for rate relief and we are delivering it," Stan Ogden, an Ameren vice president in charge of customer service, said in a statement.

Customers can find out exactly how much they'll be getting by visiting Ameren's Web site at http://www.ameren.com.

The checks and credits are part of a $1 billion rate relief package negotiated by the utilities and state lawmakers and signed into law by Gov. Rod Blagojevich two weeks ago to ease the customer outrage.

The deal rolls back the increases customers paid this year by an average of 40 percent, with the actual rebate amount tied to electric usage.

All Ameren customers will get at least $100 back by the end of the year -- $85 through the initial checks or credits and the rest through monthly credits for the remainder of 2007.

Customers who don't use electric to heat their homes will get about $130 back this year, and customers who have electric heat will get back about $400. Customers who use massive amounts of electricity will see $1,000 or more in rebates and credits.

Customers for both Ameren and ComEd, an Excelon Corp. subsidiary, are in line for bill credits in 2008 and 2009, but those get smaller as the higher rates are phased back in.

ComEd spokeswoman Judy Rader said ComEd customers will start seeing bill credits of an average of $60 in their October bills, which will be sent out over the next month starting at the end of September. ComEd bill credits for the rest of the year will average about $7 a month, she said.

Ameren spokesman Shelley Epstein said customers who don't see money back by late October or who have complaints should contact the utility.

"We think this shows a good faith effort to reach out to our customers and mitigate the high bills," he said.