By 10.30am, about 20 patients had been through the doors, and as patients were triaged and nurses and doctors got to work, removal teams continued to cart in gear from the old to the new.
The emergency department was the first to open its doors at 7am. Other wards joined it progressively during the day and more will do so tomorrow.
The emergency department, urgent care, radiology and maternity are now open; the general ward and children's wards open tomorrow. Wards are no longer named.
The Greymouth Medical Centre GP practice opens on Monday, as does allied health, blood tests and the public cafe. The final service to move is infusion, next Wednesday.
Olsen's Pharmacy Unichem Te Nikau aims to be in the Health Centre by mid-August, owner Julie Kilkelly said.
The 8500sqm building covers three floors and includes 56 in-patient beds, three operating theatres and an integrated family health centre. Unlike the old Grey Base Hospital, Te Nikau is a one-stop shop and also includes a GP practice, pharmacy and cafe.
Family Health Centre admin-business manager Meriem Wilson said it was "marvellous".
West Coast District Health Board deputy chairman Tony Kokshoorn said it was a "magnificent" facility.
"It's something every Coaster can be proud of. People around New Zealand would give anything to have a brand new hospital like we have."
Mayor Tania Gibson also welcomed the opening.
