The Royal College of Nursing (RCN) has called for urgent action as new analysis shows only one third of shifts have enough nurses.
The latest release of data from their Last Shift Survey shows the urgent need for investment in the nursing workforce and safety-critical nurse-to-patient ratios enshrined in law.
The survey of more than 11,000 members reveals just a third of shifts had enough registered nurses.
Chronic staff shortages mean individual nurses are often caring for 10, 12, 15 or more patients at a time.
"We’re now calling for safety-critical limits on the maximum number of patients a single nurse can be responsible for," the RCN said.
They found that 1 in 3 hospital shifts were missing at least a quarter of the registered nurses they needed, while in the community almost 4 in 10 shifts were missing up to half of the planned number of registered nurses.
In A&E settings, significant numbers of nurses reported having more than 51 patients to care for. In outpatients, caseloads of more than 51 patients were consistently reported.
Across all settings, 80 per cent of respondents said there aren't sufficient nurses to meet the needs of patients safely.
RCN Acting General Secretary and Chief Executive Professor Nicola Ranger said: “Without safety-critical limits on the maximum number of patients they can care for, nurses are being made responsible for dozens at a time, often with complex needs. It is dangerous to patients and demoralising for nursing staff.
“When patients can’t access safe care in the community, conditions worsen, and they end up in hospital where workforce shortages are just as severe. This vicious cycle fails staff and patients – it can’t go on.
“We desperately need urgent investment in the nursing workforce but also to see safety-critical nurse-to-patient ratios enshrined in law. That is how we improve care and stop patients coming to harm.”