The truth behind UK migration figures

Heathrow border control

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Ever wondered how many people are moving to, and leaving, the UK? If so, you're not the only one - the official figures are said by some experts to be based on not much more than guesswork.

Yes, despite few issues mattering more to politicians and the public than migration, the UK still does not have an accurate system for counting people in and out.

The e-borders scheme - which was meant to do this job - is still a work in progress, and despite government assurances to the contrary, there are some who fear it might stay that way.

Instead the government relies on the answers given by a sample of travellers who agree to be stopped and questioned by a team of social survey interviewers at Heathrow and other main air, sea and rail points of entry to the UK.

And despite the increasingly high hurdles to jump through to get a visa to come to the UK, it seems there is no way of knowing if someone is still in the country when it expires.

UK population

Crowd of shoppers
  • According to the 2011 census there are 53 million people in England; 3.1 million in Wales; and 1.8 million in Northern Ireland
  • The figure for Scotland - and the whole of the UK - will be announced in December
  • The population of England and Wales has risen by 3.7 million in a decade - the largest increase since records began
  • The growth was fuelled by increased life expectancy, a rise in fertility rates and immigration
  • The 2011 census could be the last - the government is looking into cheaper and more responsive alternatives

Keith Vaz, chairman of the influential home affairs committee says he finds it incredible that a supermarket loyalty scheme can collect and store details on the shopping habits of millions of people, yet a similar database can not be set up to record arrivals and departures.

Particularly when the coalition government sets such store by reducing "net migration" - the difference between the number of people entering and leaving the country.

So if Britain does not count everybody in as they arrive, and count them out again as they depart, where exactly do the net migration figures announced each quarter by the government come from?

The main source is the International Passenger Survey (IPS), which was designed in the early 1960s to find out how much foreign tourists were spending in the UK - something it is still used for today.

It works something like this: There are about 240 IPS officials stationed at major airports and ports around the country.

They pick out every 10th, 20th or 30th passenger streaming through arrivals or departures, depending on how busy they are that day, and ask if they wouldn't mind taking part in a short survey.

"There may be times when, owing to a particular flood of passengers, you just cannot keep an accurate count. Do not panic if this happens but keep counting as best you can," advises the Office for National Statistics training manual.

'Hopelessly inadequate'

The ONS takes the raw IPS data and adds information about asylum seekers and migration statistics from Northern Ireland, as well as figures for people who have entered the country on short-term visas and decided to ask to extend their stay, before arriving at a final immigration figure.

About 300,000 people are interviewed each year by IPS officials - about 0.2% of the 200 million who enter and leave the UK over the same period.

The IPS has been considerably beefed up in the past three years, after it came in for stinging criticism from senior figures, including Bank of England governor Mervyn King, who branded it "hopelessly inadequate".

The ONS admits the survey is still not perfect but points out that 800,000 people are sampled to find the 300,000 interviewees and it has cast its net wider than Heathrow, where most interviewers were based, to other airports around the country and ferry terminals at Dover and Portsmouth it says 95% of travellers now "have a chance" of being interviewed.

It also has the virtue of being long established and relatively cheap.

But it is entirely voluntary and despite the training manual's advice to interviewers to be cheerful at all times - "no one wants to be interviewed by an unsmiling person with a dreary monotonous voice". Although the response rate is 78%, the ONS says that only 2% of people approached refuse to take part in it.

Passengers travelling at night, when interviews are suspended, or on smaller, low volume routes also slip through the net.

The one thing the IPS has over other sources of data on immigration - such as the number of non-EU passengers passing through border control, new NHS registrations or new National Insurance numbers - is that it records how long migrants say they intend to stay in the country.

Graph How accurate are the official net migration figures?

But its major flaw, according to experts, is when it comes to measuring how many people are leaving the country.

IPS emigration estimates are based on interviews with just 2,000 people (who, the ONS point out, are found from interviews with about 400,000 interviews) - and there is currently no alternative source of data to measure them against.

This matters because the coalition government has promised to reduce net migration - the difference between those entering and leaving the country - to "tens of thousands" by 2015.


Home Secretary Theresa May hailed "the first significant falls in net migration since the 1990s" in her keynote speech to the Conservative Party conference.

What she failed to mention was that when that "significant fall", from 252,000 to 216,000, was announced, the margin of error was also revealed for the first time.

What happened to e-borders?

Tony Blair
  • Tony Blair launched the £1.2bn e-borders programme in 2003
  • It was meant to collect details from passenger lists of all people entering and leaving the UK so that they can be checked against security watch lists
  • All flights from outside the EU are now part of e-borders
  • Ports and railway stations are due to follow by 2014
  • EU flights are meant to be covered by 2015
  • But that will depend on reaching voluntary agreements with other nations - and solving commercial problems
  • The US firm handed a £750m contract by Labour to deliver e-borders, Raytheon, was fired by the coalition in 2010 for "extremely disappointing" performance
  • The company is seeking £500m in damages from the government
  • The e-borders contract was split in two with IBM and Serco given the job of getting a system in place at nine airports before the Olympics
  • The contract for the post-Olympics element of the programme - the biggest part of it - has yet to be awarded

This showed that the main source of these figures was only accurate to within plus or minus 35,000 people.

In other words, according to the ONS, the fall was not yet statistically significant.

This does not mean, of course, that net migration has not fallen, just that, according to some experts, the government's main method of measuring its progress is little better than a rough guess.

"It is very difficult to assess how well the government is progressing toward its target of reducing net-migration to the 'tens of thousands', or to evaluate the effects of specific policy changes," says Dr Martin Ruhs, Director of the Migration Observatory at the University of Oxford.

"In simple terms the government could miss the 'tens of thousands' target by many tens of thousands and still appear to have hit it - conversely the government could hit, or even exceed its target and still appear to have missed it."

The government denies that the IPS is a faulty instrument for measuring its progress on migration.

In a statement to the BBC, Immigration Minister Mark Harper said: "The International Passenger Survey already provides the ONS with a reliable method of measuring net migration.

"By 2015, we aim to reintroduce exit checks using the e-borders system, which will allow us to build an even more accurate picture of the number of people entering and leaving the country."

A brainchild of the Tony Blair era, when it seemed as if there was no problem that could not be solved by a multi-billion pound IT project, e-borders was meant to replace the old paper-based embarkation system, which was scrapped in the 1990s.

Since then departures from the UK have not been officially recorded.

So it is possible for migrants to enter on short-term visas and - unless they notify the authorities of their intention to stay longer or are really, really unlucky and are picked up in a Border Force raid - stay in the UK or leave the country years later without showing up in the official records.

It was one of the justifications Mr Blair made - and is still making - for the introduction of an identity card system.

E-borders which was primarily meant to improve security, when combined with a biometric identity card scheme, began collecting details of passenger and crews for inbound flights from outside the EU at nine airports in March.

The plan now is to extend it to ports and railway stations by 2014 and to passengers from within the EU by 2015.

But that will depend on persuading all EU countries to share passenger and crew list information - quite a number of them regard this as illegal under European free movement laws.

High hopes

And there are some, such as Keith Vaz and Sir Andrew Green, of think tank Migration Watch, who fear the project, which was meant to be up and running in time for the Olympics, may have stalled altogether.

"The government will rightly be held to account if they fail to achieve a steady and substantial reduction in net migration, whatever the technical details," said Sir Andrew.

"But it is time we were told more about the purpose and progress of the e-borders programme."

The statisticians at the ONS still have high hopes that e-borders will one day be able to provide reliable migration statistics.

But they say it will be 2018 at the earliest before they can even start incorporating data from the programme into their estimates - and there are no plans to replace the IPS as the main source of migration data.

So until the Home Office can be persuaded to come up with a different method - the men and women of the IPS will continue to put on their best smiles and try not to panic as they scan the arrivals halls of Britain's ports and airports.

And net migration statistics should continue to be taken with a major dose of salt.

Graph showing increase in migration

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  • rate this

    Comment number 414.

    Social cohesion and secutiry threats from this policy are staggering and often glossed over.
    We can't stop murderers/rapists/terrorists from entering the UK because we rely on other nations telling us about it. Once in we know how unlikely deportation is.
    Integration or enclaves of non english speaking communities which do you see?
    We are changing to suit them not the other way round!

  • rate this

    Comment number 413.

    There is both good and bad migration and people have tried to defraud the system and our country and have succeeded largely due to the human rights laws, once here they claim infringement of their human rights. Why is it that for instance Abu Hamza has been able to stay here all this time denouncing our country?

  • Comment number 412.

    This comment was removed because the moderators found it broke the house rules. Explain.

  • rate this

    Comment number 411.

    Reading between the lines on a lot of these posts, it seems that skin pigmenation has a lot to do with the "too much" brigade.

    In some ways any immigration debate is hypocritical by the government who "believe" in aeverone having the opportunity to better themselves and progress yet deny people the opportunity.

  • rate this

    Comment number 410.

    If they knew the figures they wouldn't publish them. The option of looking incompetent, is presumed to be more propitious than facing the anger that would follow if the true figures were made public.

  • rate this

    Comment number 409.


    How I wish there were more space to debate you on your points.

    MOST immigrants try very hard to integrate, but find problems in doing so.

    FEW immigrants preach hatred.

    FEW indigenous population preach hatred.

    We have more in common than we have in opposition.

  • rate this

    Comment number 408.

    The government are actively dealing with immigration issues and it’s apparent to see.
    That’s the reason for the government making the UK such a jobless, non prospering, financial downward spiral place to live, so that the immigrants will see that its better back where they came from.

  • rate this

    Comment number 407.

    This debate is not about race but about sustainability what is the optimum population this small nation can sustain without having a big impact upon the quality of life of it's people. I would suggest given the pressure to build on flood plans which recent events show is madness we have reached that point at least in England anyway.

  • rate this

    Comment number 406.

    Immigration has ruined the UK.

    Several million of our own unemployed - but outsiders can come here in droves and take the available jobs, while the government pays our home-growns to be unemployed.

    Sky-high house prices, because too many people coming here means demand for homes always outstrips supply.

    The British government couldn't care less about the problems immigration causes.

  • rate this

    Comment number 405.

    368 Graphis
    "Because the odds are that if they speak even a few words of another language, it will be English"...Please stop with the complete nonsense you are peddling. You want to see how much local councils spend on translation for immigrants and police interpretors? (do we need to spend money on imported criminality). The fact is they come in vast numbers because of the soft system.

  • rate this

    Comment number 404.

    BNP and UKIP winning more seats and running local councils.

    This is the only way the mainstream parties will realise something is wrong.......too late.

    You the mainstream parties did not listen to the concerns of the public and simply brushed them away as if to say we know better.

  • rate this

    Comment number 403.

    My home in Britain is in a London borough where immigrants are the majority, many are unemployed and more are on benefits. Not conjecture - clearly visible every day.

    I propose to emigrate with my pension to escape this ghetto. Sure, I'll be an immigrant in my new country, but I'll be a contributor, not a leech.

  • rate this

    Comment number 402.

    Over the decades, successive governments have been elected due to their (fraudulent) sound bites about curbing immigration and an EU referendum. Then it’s u-turn after u-turn! Cameron even has the hypocrisy to praise the virtues of the ‘Arab Spring’ & their DEMOCRASY. Try giving us some! Government in-action is forcing moderate voters to UKIP and some unfortunately to the BNP.

  • rate this

    Comment number 401.

    I agree! Let's hug! =D

    Glad we've got past that :-)

    what's much more important is "Let's Rock", BTW why did you retire? was love too much of a battelfield or didn't feel you belonged in the fire and ice or was it all too much of a heartbreaker :-)


  • rate this

    Comment number 400.

    This shows utter incompetence, what do we pay these people for !!

  • rate this

    Comment number 399.

    There seems to be a consensus that the immigration policy has been a shambles under successive Governments both Tory and Labour since the fifties. That being so then why, at the next General Election, will there be a stampede of people to vote for the main two political parties who have let us down for decades. I will never ever vote for one of these parties again. Suggest others follow my lead.

  • rate this

    Comment number 398.

    All very well to shout and scream about tighter controls, but are you willing to pay? The only effective way to do this is with high staffing levels on entry and exit points physically checking and recording all passports/visas. I suspect the same people will be screaming about excessive government, too many civil servants, too much tax!
    IT won't do it unless every passport in the world complies

  • rate this

    Comment number 397.

    396.Andy The Thinker
    Just now

    Totally agree with you Andy. But we have weak kneed politicians that lie to use that immigration is good for us. NO ITS NOT.
    If an immigrant wishes to come to this country, knowing fool well twhat our culture,traditions and religon are, then they accept that. If not, they have another British right. The right to go back

  • rate this

    Comment number 396.

    A peaceful invasion is Not peaceful when people come to your country and refuse to accept the culture and values of your country - and indeed denigrate those values!

    Worse still, when they preach against the very values that made the country Great, and think of you as less-worthy and themselves as superior (and above the law you follow)... Big Problems!

  • rate this

    Comment number 395.

    "Still treating some human beings as 'other' then. 'We' of course are wholly different..."

    "We" - Those hapless mugs who are laughed at if they were to call themselves an immigrant or ethnic minority in order to get any help off the government after paying taxes for decades.

    The government made the race relations act and all of it's racist divisions. It's not racist to fight that.


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