Record numbers of people are approaching welfare organisations for financial help to meet the cost of keeping Pesach.
Around 550 United Synagogue congregants have requested assistance. US community services director David Kaplan said figures had been increasing year on year.
US Chesed director Michelle Minsky - who is fronting the "Give US Your Dough" campaign in support of Pesach aid - said most of the those needing financial support were in Hackney. But there were cases in the most affluent areas.
"It's not surprising really that in these economic times, the numbers who need help rise. The last thing we want is people not to be able to afford to keep Pesach."
Help is offered in a variety of ways. Some receive Pesach parcels, others get food vouchers. Some synagogues will reimburse families if they supply receipts, normally for a spend of around £50.
"We don't means test the people who ask for help - we trust them," Ms Minsky explained. "Even in the richer areas, we get requests. Some of the synagogue care co-ordinators say their children have really learnt something about their own area, that not everyone is as fortunate as them. When you can afford it, you don't really think about other people who can't."
Norwood will give a small number of grants to families who are struggling to afford food for the festival. Last year, the charity's Pesach appeal concentrated on a family provided with a grant for basic foodstuffs. There are two autistic children in the family, which was not invited to a Seder because of the children's behaviour.
Chief executive Elaine Kerr said: "Norwood is the community's safety net and we believe it is important that people should be able to sustain their religious practice irrespective of their personal circumstances.
"Therefore, in special cases, our family support team will make small grants to help families who would otherwise find it difficult to celebrate Pesach due to the costs."
Jewish Care reported a doubling of requests for respite care over the Pesach period, with a waiting list of people.
Service manager Yehudit Amias said sometimes it was because "their families are not around and the person is not able to go with them, or they are alone and do not want to be by themselves during Pesach".