London, 15 June 2009

An amnesty for long-term illegal immigrants could be worth as much as £3billion to GDP and £846 million in additional tax revenue a year, a report published today by the Greater London Authority has found. The London School of Economics study was commissioned by Mayor of London to assess the potential benefits of an amnesty. It estimates there are 618,000 irregular migrants in the UK and 442,000 in London – the equivalent of the number of residents in Camden and Harrow boroughs.

The report found London is disproportionately affected by illegal immigration with an estimated 71% of illegal immigrants in the UK living in London and identified the impact of this on the capital’s economy, employment and public services. The report found border controls are a vital factor in controlling immigration and an amnesty would not lead to increased migration unless border controls were ineffective. It also found that 67% of irregular migrants might be eligible for an amnesty if a 5-year residency rule were applied as part of the regularisation programme.

Boris Johnson said: “This new report has introduced some long overdue facts, hard evidence and academic rigour into a debate which has far too often been dominated by myth, anecdote and hearsay. ‘So far from a financial burden, as some suggest, this new research has found an amnesty could be worth up to £3 billion a year to the country's economy.

‘The study also demolishes the argument that an amnesty would inevitably lead to increased migration to the UK and identifies effective border controls as the vital factor in controlling and deterring illegal immigration.”

Report's key findings:

• Potential benefits: An amnesty might add £3 billion p.a. (or 0.2%) to GDP and £846 million p.a. additional tax revenue for the UK as a whole.
• Potential costs: An amnesty might lead to public service costs of £410 million per annum. If the regularisation scheme enabled access to welfare benefits and housing the maximum possible cost could be around £1 billion. There would also be a one-off cost of the scheme including administration of £300 million.
• Implementation: The absence of land borders in the UK means an amnesty is less likely to encourage illegal immigration and effective border controls are a vital factor in deterring illegal immigration.
• The central estimated figure for irregular immigrants in London is 442,000 with a range from 281,000 and 630,000.
• The central estimated figure for irregular immigrants in the UK is 618,000 with a range from 417,000 to 863,000.
• Only 111,265 illegal immigrants have been deported in 10 years since 1998. If deportations continues at these levels it will take more than 50 years to deport the estimated 618,000 illegal immigrants in the UK.
• The National Audit Office estimated the cost of deporting an irregular migrant is £11,000. To deport all those currently in Britain could cost up to £4.7billion.

Click here to download a summary of the Irregular Migrants Report (1.16MB)
Click here to download the full Irregular Migrants Report (1.99MB)