For the average Greek, capital controls have now gone from threat to reality. But what does this mean in practice?
On Monday morning, employees of the National Bank of Greece, the country's largest commercial bank, were continuing to go to work in Athens' Syntagma Square -- even though the bank is closed to customers.
ATMs were shuttered, but expected to open at noon, a security guard told CNBC. The Athens Stock Exchange will be closed all week too.
Account holders can only withdraw 60 euros ($67) each day. On Sunday night, there were already queues at ATMs as Greeks tried to take advantage of the last hours before the new controls took effect. There were also queues at supermarkets and petrol stations over the weekend as people stocked up ahead of an uncertain week.
Pension payments (which are increasingly important as high unemployment means that more generations are reliant on them) are exempt from the restrictions, as are electronic transactions.
Capital flight has accelerated from the past few years' steady flow to haemorrhage in recent weeks, with more than 1 billion euros a day leaving Greek banks last week, according to Citi estimates. If you had substantial savings in Greek banks in 2011, chances are you have already moved them offshore – or even just under your mattress.
People who have traveled to Greece from outside the country can withdraw the maximum limit set by their banks -- which can be higher than 60 euros per day -- but this depends on whether there are sufficient notes left in ATM machines.
Hotels and restaurants are expected to ask for payment in cash rather than on credit card, as concerns about the day-to-day functioning of the banks grow.
Visitors from the U.K. have been advised by the government to bring "enough euros in cash to cover emergencies, unforeseen circumstances and any unexpected delays."
A week without ready access to cash is likely to focus Greek minds on the urgency of their situation. Some analysts are already warning that Prime Minister Alexis Tsipras and his Syriza party may have overplayed its hand.
"The imposition of capital controls and its immediate visible effects on the country's economy could play in favor of the opposition's strategy of blaming Syriza for the chaos," analysts at Teneo Intelligence wrote in a research note Monday.
"If Tsipras is defeated in the referendum, it is hard to see how he could remain in power, as the government would hardly be able to pass any new proposal coming from Brussels."