The cost to the NHS of smoking is around five times higher than the current figure in use - totalling more than £5 billion a year - suggests research published ahead of print in Tobacco Control.
The most recent cost estimates for the direct healthcare impact of smoking are based on 1991 data, and range from £1.4 to £1.7 billion a year, with an annual death toll in excess of 105,000 up to 2002.
The complexities of calculating the direct costs of disease ensure that these sorts of studies are not carried out regularly, say the authors, prompting reliance on figures that quickly become out of date.
For the purposes of this study, they revised the currently accepted figures by drawing on three sources of reliable data up to 2005/6, when around one in four UK adults was a smoker.
They systematically reviewed previously published research on the subject between 1997 and 2007.
They also collated information from the World Health Organization's Global Burden of Disease Project, which assesses the proportion of disease attributed to a particular risk factor by sex and region, for 2002.
And they included routine data on UK deaths attributable to smoking, which are collected monthly, for 2005.
Based on these data sources, they calculated that in 2005, around 110,000 people died as a direct result of smoking, accounting for almost one in five of all deaths (19%).
When assessed by gender, the figures indicated that smoking was responsible for more than one in four deaths among men (27%) and around one in 10 among women.
This figure is similar to previous calculations, say the authors, and "suggests that the overall numbers of deaths attributable to smoking have not changed much in the past 10 years."
Their calculations also indicate that smoking was directly responsible for a significant amount of disability and premature death, reflected by the composite measure of Disability Adjusted Life Years Lost (DALY).
Of all DALYs lost in the UK, 12 were attributable to smoking.
Finally, their financial estimates for the direct impact of smoking on the NHS came to £5.2 billion for 2005/6, which equates to 5.5% of the total NHS budget for that year - a proportion that has not changed since the early 1990s.
This annual cost is still likely to be an underestimate, they say, because it does not include indirect costs, such as lost productivity and informal care; the costs of treating disease caused by passive smoking; or the full range of conditions associated with smoking.