The preparations are all but done for the biggest Christmas Day lunch in the country.

The Auckland City Mission will serve a Christmas Day lunch to about 2000 people on Monday.

Preparations actually began at the Viaduct Events Centre as far back as 8am on Friday.

On Sunday the volunteers came in waves to do the food preparation and the clean- up after that.

There were separate groups to make desserts and to prepare the meat and vegetables.

Preparation of all food was completed by noon on Sunday.

The cooking begins on Christmas Day at about 6am and volunteers start decorating the tables at 7am.

More volunteers arrive at 10.30am and the doors open an hour later.

They'll serve up 300kg of ham, 2,000 chicken drumsticks, and 300kg of potatoes, with jelly and ice cream for dessert.

Every guest will receive a gift before going home.

Down in Christchurch about 700 people are expected for lunch in a marquee at Christchurch East School.

The City Mission there put out a late call for more donations of pavlovas stating "We can't face a Christmas without pavlovas".

About 150 people are expected for the Room at the Inn charity Christmas Day lunch in Upper Hutt.

Quinns Post Tavern owner Murray McMahon will provide the venue and other services.