Search continues for missing SA dad

There are serious concerns for an Adelaide father who has been missing since Mother's day.

Police began door-knocking on Sunday, a week after 33-year-old Michael Modesti went missing, leaving his phone and bankcards at home in Beverley.

His car was found last week in a nearby suburb.

"He last spoke with his partner by phone about 11pm on Sunday, the eighth of May, and hasn't contacted his young son since that day as well," a police spokesman told ABC radio on Monday.