Some pub landlords say they are being squeezed out of business by the high rents and inflated beer prices demanded by pub companies.A GMB union survey of 3,000 tied landlords suggests that almost a third have debts of nearly £50,000.
The GMB claims pub companies make tied landlords pay twice as much for beer.
The British Beer and Pub Association said tied landlords may pay more for beer, but did not need much start-up capital to enter the industry.
The association, which represents pub companies, said new guidelines will help tied landlords.
About half of the UK's 52,000 pubs are tied to pub companies, where they lease premises from the companies and are obliged to buy their beer from them.
Pub debtThe GMB said the high price of beer was driving thousands of their members out of business.
Previously, pub companies have said the "beer ties" situation gave people who were unable to afford to buy a pub of their own the chance to lease one.
In February, the Office of Fair Trading (OFT) reopened its investigation into "beer ties".
The OFT said it acted after the Campaign for Real Ale applied for a review.
Four months earlier the OFT said it had found no evidence that competition was being harmed by landlords having to buy beer from pub owners.