Researchers claim smoking costs the NHS five time more each year than previously thought.
The team from the Department of Public Health at Oxford University suggest that the actual cost of illness and disability linked to smoking is more than £5bn a year.
They wrote in the journal Tobacco Control that this cost is putting a "huge burden" on the health service in the UK.
Previous studies suggested the cost of smoking to the NHS in 1991 was between £1.4bn and £1.7bn.
But new analysis has found the actual figure in 2005/06 was £5.17bn, although researchers say even this could still be an underestimate.
The findings show that in 2005/06 the largest proportion of the money, £250.8m, spent on illnesses caused by smoking was on cardiovascular diseases.
The team also explained that almost one in five deaths in 2005 were due to smoking.
They wrote: "We estimate that 109,164 deaths (18.6% of all deaths) in the UK in 2005 can be attributed to smoking (27.2% of male deaths and 10.5% of female deaths).
"This figure is similar to previous calculations and suggests that the overall numbers of deaths attributable to smoking have not changed much in the past 10 years."
Copyright © Press Association 2009
Department of Public Health at Oxford University