The phrase "admin office" is correct and usable in written English.
It can be used to refer to an administrative office or department within an organization.
Example: "Please submit your request to the admin office for processing."
Alternatives: "administrative office" or "administration department."
I thought maybe I had fallen and was in an admin office on campus.
We are clearly in a psychiatric institution complete with treatment rooms, library and glass-walled admin office.
Tellingly, as a music journalist the big thing I've noticed this past year is the sheer number of bands I've interviewed during their lunch breaks while working jobs at, say, the local council or in the admin office of universities.
"We are clearly in a psychiatric institution complete with treatment rooms, library and glass-walled admin office … Ian Rickson, making his debut as a Shakespeare director, has come armed with a strong concept: this is Hamlet played as the Freudian dream of a disturbed in-patient".
It shows in his campaign, which boasts a large, bustling office – complete with meeting area, admin office and wine chiller – in the heart of Hove's main strip, and which can muster up to 70 volunteers every Saturday for door-knocking and leafleting duties.
"Children with allergies are sometimes raised as a concern but we have to encourage the school to make reasonable adjustments - maybe a dog could go into the admin office for that period.
The admin offices have gone, clearing a whole floor for more art.
The old admin offices at the factory house two banks: Polski and Deutsche.
It seem to us that the company simply doesn't have enough support staff and problems like this are backing up at its admin offices.
The money was spent on energy efficiency measures in Peterborough's public buildings – its leisure buildings, admin offices, schools and car parks.
The desktop configurations of computer labs and admin offices can be standardized and managed centrally.
