Hospital chiefs have massively cut cash losses to foreigners who fail to pay for their treatment.
Calderdale and Huddersfield NHS Foundation Trust has historically lost tens of thousands each year to overseas patients who were not eligible for NHS treatment.
Figures released by the Department of Health show the NHS has been forced to write off £11 million worth of bills from foreign patients last year, up from £2m a decade ago.
But health managers in Huddersfield are this year celebrating slashing the bad debt from non-paying foreigners by almost 90%.
Losses for treating ineligible patients at Huddersfield Royal Infirmary and Calderdale Royal Hospital have dropped from £76,000 in 2011/12 to just £11,000, in the last financial year.
The improvement has come after the Trust overhauled its overseas payments collection system.
Clinicians are now advised to make a judgement on whether treatment of an overseas visitor is an emergency and essential or if it would be better for the patient to wait until they have returned home.
Overseas visitors’ details are sent to the Trust’s finance department as soon as they are discharged so their bill can be drawn up and issued without delay.
The Trust says it also informs the Department of Health when a payment has not been made.
Director of finance Keith Griffiths said: “We are pleased to see that the new, processes are already making a difference.
“In the current climate it is absolutely vital we get in all the money we are owed for the care we provide.
“We would only ever write-off a debt when it is costing more to pursue than the bill itself is worth.”
Free NHS hospital treatment is available to British residents but overseas patients are charged for the full cost of any treatment they receive unless a specific exemption applies.
Urgent treatment is always available to overseas visitors, regardless of their residence status or ability to pay, but non-urgent treatment should not go ahead without the NHS first receiving payment.
In 2009, West Middlesex University Hospital, in west London, became the first to tell foreign patients they must pay in advance.
Some hospitals in the London region have been reported to be owed more than £2m from treating tourists and non-British residents.
The Trust’s losses report also reveals about £10,000 per year is lost for “other” reasons.
A Trust spokeswoman said: “These are primarily prescription charges where drugs have been issued at point of care, for example in A&E, and the individual has still not been able to pay for them.”