Britain imported about 43 million more litres of Australian wine last year as coronavirus lockdowns boosted demand.
Trade body Wine Australia said volumes increased by 19% to 266 million litres in 2020, with sales also buoyed up in the run-up to the end of the Brexit transition period.
Australia is the top-selling producer for wine bought in shops in the UK meaning that it has benefited from people staying at home while restaurants have been closed.
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That has helped offset a slump in revenues from another big export destination, China, which imposed tariffs of up to 212% on Australian wine exports amid tensions between the two countries.
Australia's wine exports grew by 0.5% by volume over the year to 747 million litres but that was at the expense of price, which fell by 1% to an average A$3.87 (£2.14) per litre.
That meant that sales by value to overseas markets dropped by 1% to A$2.89bn (£1.6bn), thanks to a drop-off towards the end of the year after China imposed tariffs in November.
Wine Australia chief executive Andreas Clark said: "Wine businesses are resilient and are already adapting to these changed market conditions, increasing their engagement in markets other than China, particularly the UK, USA, Canada and the domestic market."
The figures showed that the UK extended its lead as the top destination for Australian wine by volume, followed by the US, where volumes fell by 1% and mainland China, where they dropped 29%.
By value of sales, China remained on top though sales dipped by 14% to A$1.01bn (£560m) and the UK was second, up 29% to A$456m (£252m).
"The UK continued the strong growth that commenced at the advent of the pandemic due to increased demand, which was then boosted in the months leading up to Brexit," the report said.
A Wine Australia spokesperson told Sky News: "Australian wine has been the number one seller in the retail market for nearly two decades and as restaurants and cafes have been closed during the pandemic Australian wine has benefitted from the upsurge in retail sales."
The pre-Brexit boost was attributed to merchants who package wine in the UK before selling it on to Europe wanting to avoid border hold-ups by doing so earlier in the year.
