Reality Check: How much pressure do EU migrants put on NHS?

Those who campaign for the UK to leave the European Union say migration has put huge pressure on public services, including the NHS. What's the true cost of EU migration to the NHS?

It's relatively easy to estimate the cost of short-term visitors because the Department of Health has had a go already.

They put the cost to the whole of the NHS from visitors and non-permanent residents who come from the European Economic Area (that's the EU as well as Iceland, Liechtenstein and Norway) at around £340m a year.

That figure includes the cost of treatment received by so-called health tourists - people who visit the UK purely to use the health service.

This is a relatively small proportion of the NHS total annual expenditure, which for England alone was £113.3bn in 2014/15

What about EU citizens who live and work here? There aren't any figures for how much they cost the NHS.

We do know there are around three million people from other EU countries resident in the UK and all are entitled to use NHS services. That definitely adds to demand.

But those people would not be forced to leave the UK, even if the UK left the EU.

No Leave politicians or campaigners have suggested that EU migrants already here should leave if the UK left the EU.

And some lawyers argue that the Vienna Convention would let EU citizens settled in the UK and UK citizens living in other EU countries stay where they are, if the UK decided to leave the EU (although it's worth noting that two EU countries - France and Romania - are not signed up to the convention).

How much leaving the EU would restrict future migration from the EU would depend on whatever deal the UK struck when it left the EU.

If the UK were to retain full access to the single market, the rules on the freedom of movement are likely to stay the same. If the UK leaves the single market, it would be free to decide on its own immigration policy.

Meanwhile, campaigners for Britain to remain in the EU warned that leaving it would damage the NHS. TUC General Secretary Frances O'Grady said that "Brexit would plunge the NHS into a staffing crisis".

Just how dependent is the NHS on staff from other EU countries? NHS England provides figures that show a total number of all staff (part and full time) coming from the EU countries was just over 53,000 or 4.6% of the total NHS workforce.

A total of 9% of NHS England's hospital doctors came from the EU and the number of EU nurses and health visitors accounted for 6% of the total. Doctors from the European Economic Area (the EU plus Norway, Liechtenstein and Iceland) account for 4.2% of full-time GPs working in England (excluding locums).

The NHS in Scotland, Wales and Northern Ireland don't publish the breakdown of their staff by nationality.

A British exit from the EU would be unlikely to create an immediate NHS staffing gap for the reasons which were explained earlier: Those already settled in the UK are likely to be allowed to stay.

How a future post-Brexit government would fill the potential NHS staff shortage, if it restricted EU immigration numbers, is a matter of pure speculation at this stage.

Reality Check verdict: There are no figures to show the exact cost to the NHS, but the three million EU citizens already here are likely to stay even if we leave the EU.

UPDATE: This article was updated on 17 June 2016 to include Leave campaigners' position on EU citizens already on the UK, to point out that France and Romania are not signatories to the Vienna Convention, and to add numbers of GPs working in the NHS in England.

READ MORE: The facts behind claims in the EU debate