Working families are just 19 days away from the breadline, according to financial services firm Legal and General which has one of its main offices in Hove.
L&G said that average resilience had fallen 21 per cent from 24 days since 2020 – and that “cutting back has become the norm”.
The firm’s latest Deadline to Breadline report said that people overestimated by almost six weeks how long they could fund basic living costs if they lost their income.
These included costs such as rent or mortgage payments, loans and credit card repayments, utility bills and food.
And, the report said, many of the poorest workers had no financial safety net in the event of losing their salary.
The figures were averages and Brighton community projects said that vast inequality locally meant that many people were more financially vulnerable than the L&G report suggested.
Initiatives to combat the loss of financial resilience as concerns grow about the cost of living include a number of community efforts to help those who are struggling.
Brighton and Hove City Council started a cost of living crisis appeal in May which has generated £37,118 donated by 314 supporters to date.
The fund is helping local people in hardship with their food and fuel costs through vouchers, food parcels and low-energy items such as electric blankets and slow cookers.
Wave Community Bank, formerly the East Sussex Credit Union, is holding a seminar about the cost of living crisis at 3.30pm next Thursday (8 September).
The webinar will provide free tips to members on how to manage a budget each month, managing debt and how to check what benefits are available.
A Brighton community pub, the Bevy, ran a programme of free summer activities that give children a free hot meal and laid on family activities including seeing reptiles, fixing bicycles and making pizzas.
Warren Carter, chair of the Bevy, told BBC Sussex: “We did meals on wheels through the pandemic and we’re working with EBFC (East Brighton Food Co-op) who deliver about 900 meals around.
“We’re always thinking about new ways to bring people into the pub and make it affordable.
“Unfortunately, we are cutting down the hours we open. Not only have we got inflation and skyrocketing energy bills, it’s really hard to find staff.
“You add it all together it’s like a lovely Sunday morning hangover.”
The Legal and General report said that, with average household savings of £2,431, debts of £610 and average daily expenses of £93, the average household would run out of money in less than three weeks if they were to lose their income.
Even more affluent households were being more cautious, L&G said, with 61 per cent of those with a household income of more than £50,000 cutting back on essentials.
L&G chief executive Bernie Hickman said: “Our latest research presents a challenging picture for working households across the UK.
“We often talk about managing money month to month but, as our findings indicate, for some it’s a case of day by day.
“The cost of living crisis is squeezing the purses of people all over the country, leaving households of every shape and size with money worries.
“The fact is there is only so much people can do to manage their budgets in these difficult times but there are resources available that can help.”