As an export market, Greece is worth £1 billion a year to the UK, representing just 0.3% of overseas sales.
But it is the wider fall-out of the crisis for the eurozone and that will cause most anxiety for British companies as well as investment funds including pensions.
The single currency bloc is the UK’s biggest trading partner while industry data suggests there is £55 billion held in unit trusts investing in Europe.
Many of London’s biggest listed firms have much of their business on the continent, or trade with it, so economic distress from a chaotic Greek exit would be likely to wash across the Channel.
It means that while the outcome of the crisis remains uncertain, the FTSE 100 Index is subdued with investors cautious over the outlook. The top-flight index has fallen by 5% since the start of June.
UK-owned banks would stand to lose a maximum of 12.2 billion US dollars (£7.7 billion) should Greece’s economy implode, according to latest Bank of England statistics
But while a large sum, this represents a small “ultimate risk” compared with that riding on much larger world economies such as the United States, where the figure stands at 965 billion US dollars (£607 billion).
Among top UK-listed firms with operations in Greece are Vodafone, whose income from the country represents 2% of group revenues.
Last year it bought a controlling stake in broadband and fixed line provider Hellas Online for 72.7 million euro (£52.1 million).
Electrical to mobile retailer Dixons Carphone also has a large presence in Greece and chief executive Seb James earlier this month told the Independent it had drawn up a detailed plan in case of a euro exit.
Greece desperately needs to unlock bailout funds worth 7.2 billion euro (£5.2 billion) to pay upcoming debts, but talks with creditors are deadlocked over their demands for reforms and budget cuts.
It faces a looming deadline on June 30 when it is due to pay 1.6 billion euro (£1.1 billion) to the International Monetary Fund (IMF).