POWYS had the lowest percentage of emergency ambulance calls reached within an eight-minute target time in July.
Latest figures published by the Welsh Government show the Welsh Ambulance Service surpassed the response time in all local health board areas in Wales for the second month in a row.
Performance ranged from 65.3% in Powys to 80.7% in Cardiff and Vale. The target time is that 65% of "red" calls - immediately life-threatening situations - are responded to within eight minutes.
The median response time to red calls across Wales was 5 minutes and 5 seconds. The service handled 1,277 calls per day on average, up 3.4% on the daily average in June 2016.
July was the second successive month the national target was met in all local health board areas since the introduction of a new clinical response model pilot last October, which prioritises the most critically-ill patients.
Health Secretary, Vaughan Gething said: “It is very encouraging to see that all local health boards in Wales have surpassed the national target for red calls for the second consecutive month, despite steadily rising demand. In July there were over 39,500 emergency calls made to the Welsh Ambulance Service – an average of 1,277 calls per day.
“I want to thank Welsh Ambulance Service staff for their dedication to providing the help people need quickly, in spite of these pressures.
“Today’s statistics show that the new model we introduced last October is contributing to a rapid emergency response service for patients who really need it. People should feel confident the new system is putting a greater focus on the quality of care people receive and their outcomes.
“We have much to be proud of here in Wales, however we will not be resting on our laurels. The Welsh Ambulance Service – and the wider health and social care system – is already planning for the coming months and the difficult winter period."