The NMC surveyed 3,496 people who left the register between June and November 2017 and found that 47% of respondents from the European Economic Area cited Brexit as a key reason for leaving.
Research by the regulatory body found that, between April 2017 and March 2018, 3,962 EU nurses left the register, a 29% increase on last year.
Over the same period, the number of nurses joining from the EEA was just 805 compared to 6,382 – a decrease of 87%.
Jackie Smith, NMC chief executive and registrar, said the figures were “a major concern”.
“We asked people why they were leaving and, for the small number of EU nurses and midwives who responded, it’s clear that Brexit is playing a part, while retirement and staffing levels are clear factors in the decision of UK nurses and midwives to leave the profession.”
Janet Davies, chief executive of the Royal College of Nursing, said: “The number of nurses is being dragged down by a botched Brexit.
“Nurses returning home, or giving Britain a miss entirely, are doing so because their rights are not clear enough.
“Theresa May must use every opportunity to say they are welcome here and valued in healthcare.”
Liberal Democrat Brexit spokesperson Tom Brake called the figures “deeply concerning” and stressed that the UK’s health service was founded on the hard work of people from around the world.
The number of nurses and midwives joining the register from outside the EU rose for the fourth consecutive year, with 1,093 more of these practitioners on the register than in March 2017.
A Department of Health & Social Care spokesperson said: “It is encouraging to see the highest increase in the number of nurses and midwives from the UK joining the register for the first time in four years.
“We know staff have never worked harder, which is why we gave a pay rise to more than 1.2 million dedicated workers in the Agenda for Change pay deal, continue to work to improve retention and flexible working and have created thousands more training places to increase the number of nurses in the future.”
