A&E hit a record high in July, with a record 2.5 million attendances amid two heatwaves.
Three of the busiest months ever recorded were between May and July.
However, more patients were seen, treated or discharged within four hours tan in June and performance improved to 75.4 per cent.
The NHS also delivered its best performance against the 18-week target for planned care for nearly five years, with 65.8 per cent of patients waiting within 18 weeks for treatment in June – the best performance since September 2021.
Ambulance teams took on 829,675 incidents in July – the fourth-highest total on record and the second-highest outside winter.
999 calls answered rose 6.5 per cent on last July to 898,503. Category 2 ambulance response times also improved by 2 minutes and 42 seconds since last month.
Professor Frankie Swords, NHS National Medical Director, said: “Like many members of the public, NHS staff are enjoying the lovely weather outside of work, but the heat is making day-to-day working more challenging while also driving up pressure on services.
“But staff are as ever demonstrating outstanding professionalism, flexibility and hard work in the face of this summer surge – seeing more patients, more quickly, while bringing down the waiting list despite record numbers of people being referred for treatment.
“With temperatures peaking today, please take sensible precautions to stay safe: keep hydrated, avoid the sun during the hottest part of the day especially if you are clinically vulnerable, and check in on older or vulnerable friends, relatives and neighbours.
“While the NHS is busy, it is here for anyone who needs it, so please continue to call 999 in a life-threatening emergency and otherwise use NHS 111.”
Health and Social Care Secretary Yvette Cooper said: “I want to thank NHS staff for their extraordinary efforts over this hugely challenging summer.
“Despite the extreme heat and record demand that NHS staff have faced, more than three quarters of patients were seen within four hours in A&E, a record 2.65 million diagnostic tests and checks were carried out in a single month, and the waiting list has fallen in the month of June for the first time since 2011.
“But today’s figures also show how much of an additional burden is placed on the NHS during periods of extreme heat, and I have made clear that we must start planning for summer pressures in the NHS in the same way we do for winter.
“That’s why I’m working closely with NHS leaders to put those plans in place, and ensure that our staffing, beds and emergency services are prepared for the demand we know is likely to come, and that our health service can keep delivering for patients, no matter the weather.”
