Earned income from visitor admissions, sales and catering finances 96% of the yearly running costs at Beamish.
Contributions also come from the eight local authorities which make up the museum joint committee.
With the visitor so vital, the museum continues to add to its attractions.
Architects are working on the final drawings for a £6m visitor centre, and plans are also being drawn up for a lamp cabin at the Colliery Village to display the museum's collection.
The facade of the current entrance building came from an 18th Century coach house and stable block from the now demolished Greencroft Hall which stood in Lanchester in County Durham.
But a bid by museum founder Frank Atkinson to have the structure listed had been turned down.
Museum director Miriam Harte says of the vision for the future: "The Beamish Valley setting of the museum is a key part of the experience and the landscape contains a lot of information, and that is something we are not currently making enough use of."
There is potential in the remains of water-powered mills on the Beamish Burn, and tow ponds which are sites of special scientific interest.
The mills provided power for the making of iron, oil, fulling and the grinding of corn and flint for the Sunderland potteries.
There are plans to re-open the water courses to power a mill and forge, and create a rural village set in the 1800s complete with church.
St Helen's Church from Easton in Cleveland, dating from the 17th Century, is in storage.
On the proposals list is a Town museum - a museum within a museum - which would allow the display of many currently stored items, a chemist's shop, baker's, doctor's surgery and terrace of Tyneside flats.
Parts of South Shields magistrates' courts are in storage and the collection from Durham County Police Museum is now at Beamish, which may combine to create a courts complex.
Also in storage are pieces of Newcastle's Handyside Arcade.
An arcade at Beamish would include small shops such as a pawnbroker's, photographer's studio, post office and toy shop.