Jewish Care is using its Pesach appeal to make a dent in the £4 million shortfall for its £44 million care campus in Golders Green, due to open in the summer.
The charity is looking to raise £250,000, covering items such as 1,000 mezuzot, costing £50,000, for the 160,000 sq ft site.
"The Maurice and Vivienne Wohl Campus is part of our vision for the future," said Jewish Care chief executive Simon Morris. "It will offer the community a network of care and support services fit for the 21st century."
Clients would be "supported and cared for in an environment where their culture and beliefs are not just understood and respected, but are central to their life".