Lawrence and Topeka postal officials want people to learn their mailing address.
"This may sound silly,'' said Lawrence Postmaster William Reynolds, "but there are a lot of cases when addresses are just incomplete."
"The address might be 255 North 15th Court. They might leave off the North or the Court. That is critical in sorting mail."
The Lawrence post office recently mailed cards to most area residents in an attempt to coax them into using accurate ZIP codes, Reynolds said.
He said the Topeka office is part of a national program to convince businesses and homes to use the complete and correct addresses. The office is urging folks to use the basic ZIP code and additional four-digit number.
"Your address is coming in the mail this week," a U.S. Postal Service ad said. "You may be surprised to find it's different from the address you're now using."
Reynolds said Lawrence and Topeka post offices have installed automated equipment to sort mail. The system works best when mail carries the full address, he said.
"Lawrence is an excellent example," he said. "Take the KU student apartments. A lot of those residents change every six or 12 months. It's impossible for us to sort by name."
Mail usually can't be delivered to the apartments when letter writers leave the apartment number or other critical information off the envelope, he said.
"We cannot sit and look up the addresses," he said. "And no one can memorize them."
Reynolds said some Lawrence residents have complained about mail service since the local office converted to the automated sorting system.
"What we're finding is that 15 to 20 percent of people sending mail to people in this town are using wrong ZIP codes," he said. "A wrong ZIP code can delay delivery one day."
He encouraged people uncertain of their ZIP code to call the post office. ZIP codes also are included in the Southwestern Bell Telephone directory.