As you asking for the contact details of the Delhi regional office of the Indian Overseas bank the contact details are given below :

Delhi regional office
RCC code 805

Address :
2,III FLR
RACHNA BLDG,,RAJENDRA PLACE
PUSA ROAD,PATELNAGAR POST
NEW DELHI
Pin : 110008
DELHI

Contact no :
011 25761904
011 25810779
011 25731322
011 25757271
011 25757254
011 25826489

for knowing details of the any other regional offices of the Indian Overseas bank you may go to the official site of the Indian Overseas bank

the page may look as follow:
Indian Overseas bank



there you may see the link of regional office on the bottom right corner of the page click on it

it may redirect you to the page there you may found the contact details of the regional offices of the Indian Overseas bank

for your convince here I am giving you the snapshot of that page

Indian Overseas bank regional office