A number of Washington residents this week received duplicate utility bills, or may have gotten another person’s bill, due to a problem that occurred last week during printing and mailing of the bills.

City Administrator Jim Briggs said about 20 customers came to city hall Tuesday morning to report the mix ups.

In some instances, residents received more than one copy of the latest bill. In others, the bill of a neighbor was included in their envelope, Briggs said.

“If you got duplicate bills, you only have to pay it once,” Briggs said. “If you got a neighbor’s bill and you know them, you can deliver it to them or bring it to city hall and we’ll see that it’s delivered.”

Briggs said the staff is working to find out what caused the snafu. It may have been due to a problem with the printing software, he said, or with the equipment that sorts and stuffs the bills into envelopes.

Briggs estimates that 1,000 to 1,500 customers may be affected.

The bills were mailed at the end of last week, he said.