Lawrence Township is occasionally and mistakenly referred to as Lawrenceville. The confusion is partly caused because the local post office is located in the Lawrenceville CDP and the Postal Service once instructed Lawrence Township residents to use Lawrenceville, Princeton or Trenton as their mailing address. In 1973, voters approved a nonbinding referendum to petition the U.S. Postal Service to adopt a single municipal post office address known as Lawrenceville for the entire township; The effort failed. A township resident appeared before Township Council in July, 2007, to request to designate the 08648 ZIP code for Lawrence Township. Council approved a resolution in support of the request that was then forwarded to the U.S. Postal Service. Township officials had fought, off and on, for the change since 1969, when then-U.S. Rep. Frank Thompson tried unsuccessfully to convince U.S. Postal Service authorities to grant a Lawrence name tag for the entire township, according to a letter on file at the Municipal Clerk's Office. The United States Postal Service notified the township authorities in October 2007 that the preferred designation for the 08648 would be changed to "Lawrence Township".