The percentage of outpatients waiting more than 18 weeks for NHS treatment is at its highest level since 2008, according to a new report, which also says more hospitals are falling into deficit.
Analysis by the King's Fund health think tank shows 3.6% of outpatients waited more than 18 weeks for treatment in November 2013, the highest level since October 2008, when the figure was 3.7%.
In addition, almost one in 10 (9%) inpatients waited more than 18 weeks for treatment, the highest since November 2011 when the proportion was almost 10%.
Today's study also found that more than one in five (22%) hospitals are set to be in deficit by the end of this financial year, according to a survey of NHS trust finance directors by the fund.
This is higher than previous surveys, and the report says the NHS will struggle to meet its target of making £20 billion of efficiency savings by 2015.
Just under two-thirds of trust finance directors rated the risk of failure to meet the challenge as "high or very high", the study said.
Fewer than half (47%) of finance directors said they expected to meet their productivity targets for the current financial year.
Meanwhile, 61% of finance leads from clinical commissioning groups (CCGs), which commission NHS services, said they were confident of meeting their productivity targets this year.
But one in eight (13%) expect their CCG to be in deficit at the end of the year.
And more than one in three (36%) of directors of adult social services also forecast deficits.
Regarding the extra £400 million announced by NHS England to help A&E departments through the winter, almost 30% of NHS trust finance directors thought the impact of the extra money would be marginal.
Only 13% said the extra funding would have a significant impact on the pressures their organisations were likely to face over the winter months.
The report said: "Looking forward - in time, if not in anticipation - this quarter's survey found finance directors more depressed than ever about the financial state of their local health and care economies.
"Eighty-six per cent of trust directors were fairly or very pessimistic about the next year financially, as were 65% of CCG finance leads and 63% of directors of social services.
"Nearly a third of trust finance directors say they are very pessimistic - the highest proportion since we began monitoring."
Professor John Appleby, chief economist at The King's Fund, said: 'Despite warnings about a potential crisis in A&E, most hospitals are coping with winter pressures so far - a tribute to the hard work of staff in A&E departments.
"However, the growing number of hospitals set to overspend their budgets shows that for some, it is no longer possible both to maintain the quality of services and balance their books."
Some 79 out of 235 NHS trust finance directors responded to the survey.
Of 195 CCG finance leads contacted, 58 responded. And out of 152 directors of adult social services, 47 replied.
Shadow health secretary Andy Burnham said: " David Cameron promised not to cut the NHS but that is precisely what is happening across the country as NHS organisations struggle to balance the books. As financial panic spreads, services are going downhill.
"This growing financial crisis in the NHS has its roots in David Cameron's disastrous decision to break his promise of 'no top-down re-organisation'.
"It created confusion when the NHS needed stability and distracted attention from the financial challenge at the worst possible time.
"When people see the growing number of NHS organisations in deficit, it will add to the pressure on the Prime Minister to justify spending £3 billion on consultants, lawyers and unnecessary redundancy payments.
"Alongside that, severe cuts to social care have intensified financial problems in the NHS.
"The cutting of support from older people in the home has been a false economy and left thousands more older people trapped in hospital. This can't go on.
"Staff morale is at an all-time low because of this Government's gross mismanagement of the NHS.
"Doctors and nurses pleaded with the Prime Minister to halt his re-organisation because they knew it would leave the NHS weakened and on the wrong path.
"They were right but Cameron refused to listen and must now accept responsibility for solving a financial crisis of his making. It is no wonder that people have concluded he can't be trusted with the NHS."
The King's Fund report refers to percentage of patients seen.
A health spokeswoman for the Conservatives said the actual number of patients now being seen was higher.
More patients are going through the system than previously.
She said: "These statistics miss the big picture. The fact is the numbers waiting longer than 18, 26 and 52 weeks is lower than any time under Labour, and there has been a big drop in the number of patients waiting longer than 18 weeks - 196,000 fewer patients than in October 2008.
"Even when you just measure outpatients, more patients are being seen within 18 weeks than they were under the last Government.
"Labour's desperate attempts to run down the NHS strong' performance are wearing thin; we have reversed years of declining productivity by dismantling their bloated bureaucracy and putting doctors in charge."