The rally was driven by basic resources-linked stocks and investors finding a strong appetite for risk.
It also came on a day packed with central bank decisions.
The pan-European STOXX 600 index was up 0.7% just after 0900GMT.
It hit a record of 510.07 points during the opening minutes of trade.
The basic resources index led sectoral gains with a 2.7% jump.
Prices of most metals climbed after the U.S. Federal Reserve stuck to its projection of three rate cuts for this year.
Gold also soared to record highs.
The Fed's rate-cut outlook also helped investors find a risk appetite.
Technology and rate-sensitive real estate shares both advanced over 2% each.
On Thursday morning, a key PMI survey showed business activity in the euro zone came close to stabilizing and inflationary pressures eased.
U.S. business activity data for March is also due later in the day.
There was a surprise for investors when the Swiss National Bank cut its main interest rate by 25 basis points to 1.50%.
That made it the first major central bank to pull back tighter monetary policy aimed at tackling inflation.
In corporate updates, fashion retailer Next led the way with shares rising 4.8%.
The British firm kept its guidance for sales and profit in the current year.
It also reported a slightly better than expected rise in profit for 2023-24.
