A trend by pubs to serve wine in bigger glasses is hiding price rises and could lead to increased health and drink-driving risks, a new guide warns.
The guide wants the 125ml glass to be adopted as a standard size
The 175ml glass is being brought in to replace the standard 125ml measure - the basis for a unit of alcohol.
But the Good Pub Guide 2006 says drinkers are often not aware how much alcohol the larger glasses contain.
Meanwhile, the guide's editors say the average price of a pint of beer in the UK is now £2.24, up 4% on last year.
In the survey of 1,100 pubs, Surrey was found to be the most expensive area for a pint of real ale, at an average of £2.51, followed by London and Berkshire.
Lancashire was found to the cheapest area, at an average of £2, followed by Cheshire and Nottinghamshire.
The guide also notes a handful of pubs are now charging £3 a pint.
The Good Pub Guide is calling for all pubs to adopt the 125ml wine glass as a standard size.
It says the unit of alcohol is a recognised measure for safe driving, diets, and health.
"People are unwittingly putting themselves over the limit and also having to spend more for wine which they perhaps don't want," said the guide's editor Alisdair Aird.
"Your first reaction is to think it is generous but it is a concealed cost increase which may be putting you at some risk."
According to government guidelines, men should not drink more than three to four units of alcohol per day and women should stick to two to three units per day.
But the Department for Transport says reaching the legal limit for driving is dependent on the weight, sex, age, food intake and metabolism of individuals.
The guide found that real ale sales are on the increase after years of decline.
The Duke of York was named pub of the year
"Interestingly, reports from our many women readers are now increasingly mentioning real ale rather than some other drinks," say the editors.
The trend of non-smoking pubs looks set to continue and three-times as many smoke-free premises are listed in the guide this year.
Pubs are also said to have become far less dependent on drinking than they used to be, with food now an important element of the industry.
The Duke of York at Iddesleigh in Devon was named pub of the year.