Research by moneysupermarket.com shows up to £112 billion is available for UK cardholders to borrow, in addition to the £64.7 billion of debt already on their credit cards.
Rob Kenley, head of credit cards at moneysupermarket.com, says this proves that consumers are – on the whole – not using their credit cards irresponsibly.
"Having credit is no bad thing as long as it used prudently and these promising figures show, on the whole, consumers are behaving sensibly," Kenley says.
Of Britain's 44.2 million adult consumers, the most common credit limit (11 per cent) is between £2,501 and £5,000.
However, there are four million people with more than £20,000 of credit at their fingertips (nine per cent), helping push the average limit per cardholder to over £5,630.
The research also found young people are less likely to lead a 'buy now, pay later' lifestyle with 52 per cent of those aged 18 to 24 not having a credit card, compared to 16 per cent of the over 55s.
Of those who have a credit card, the youngest group also has the lowest average credit limit of £2,109 compared to over £6,750 for the 35 to 44 age group.
Rob Kenley says: "Our findings are worrying, yet encouraging at the same time.
"Almost four million cardholders could each get into over £20,000 of credit card debt yet the average outstanding balance for all cardholders is £2,060, suggesting consumers could be getting savvier about the perils of too much borrowing on plastic.
"Having credit is no bad thing as long as it used prudently and these promising figures show, on the whole, consumers are behaving sensibly.
"In the run-up to the festive season, we are urging cardholders to be wary of overspending – it’s easily done but the New Year financial hangover could be painful.
"It would be a £177 billion headache for the nation if everyone maxed out their credit cards on a crazy splurge. To put it into context, that is almost equivalent to the UK's health and education budgets put together."