Net immigration is ~300k.
Net immigration is not a very informative number by itself. A more useful metric is net immigration per 1000 population per year. Let's see how the UK is doing on this metric (using mostly 2015 figures from
Australia: 5. 65
South Korea: 2.60
It therefore appears that the UK net migration levels are broadly in line with other reasonably prosperous countries. If anything, they are on the low side among anglophone countries. For example, Canada's net migration rate is over twice the UK's - and they considering increasing it further. It does not seem to cause a crisis in Canadian health care, education, or housing; rather the overall economic and social effect of high immigration is clearly positive for Canada. One might be tempted to think that the difference is in the much higher population density; however, South Korea is much more densely populated, but does not seem to consider net migration level identical to UK's as a problem.
This all makes me suspect that the "immigration crisis" in the UK is largely a manufactured problem.