Patrick Hutchings, 26, was last seen driving to work by his stepfather. That was a month ago.

Mr Hutchings left his Mascot home about 8am on October 31, leaving his mobile phone and personal items at home.

Missing ... Patrick Hutchings.

Botany Bay Local Area Command crime manager Detective Inspector Mike Birley said he did not make it to work that day and had not contacted his family.

"It is unusual because he was living in a family environment, he had a good relationship with his parents, and nothing happened to prompt this - there was no argument," Detective Inspector Birley said.