The benchmark S&P/ASX200 index on Thursday rose as high as 7,703.8 at 4pm AEDT, eclipsing its previous intraday high of 7,703.6 from February 2.
Following the minute-long 4.10pm daily auction, the index officially closed up 38.3 points, or 0.5 per cent, at 7,698.7. That's just shy of its highest-ever close of 7,699.4, also from February 2.
The index began Thursday down by as much as 0.4 per cent during the first hour of trading but gained ground all afternoon on dip buying and possibly as institutional traders readjusted their portfolios at months-end.
For February the ASX200 finished up 0.2 per cent, its fourth straight month of gains, while the broader All Ordinaries finished Thursday up 42.4 points, or 0.54 per cent, to 7,959.5, its highest close ever.
"It's been a big day, hasn't it," IG market analyst Tony Sycamore told AAP.
"I would have preferred it to be a little more convincing - somewhere around 7,015 would have been nice - but we finished with our fourth month of gains; the ASX200 hasn't gone down much since October."
The Australian market now has momentum heading into an overnight readout of the US Federal Reserve's preferred inflation metric, the Personal Consumption Expenditures index, which could provide a springboard for further gains, Mr Sycamore said.
"I do think we're setting up for a push up towards 7,900, even 8,000 - that'd be quite a ring-the-bell type moment," Mr Sycamore said, adding 7,900 might achievable by March or April.
In Australian dollar terms, Bitcoin also hit a record high of more than $96,000 on Thursday, having gained nearly 10 per cent in the past 24 hours and more than 20 per cent in the past week.
Ten of the ASX's 11 sectors finished higher on Thursday, all except utilities.
The interest-rate-sensitive property sector was the biggest gainer, rising 1.7 per cent as Goodman Group added 3.8 per cent.
Star Entertainment Group was the second-biggest gainer in the ASX200, rising 8.3 per cent to 52c after the casino operator announced it had returned to profitability in the first half with a $9.1 million statutory profit, after a horror $1.3 billion loss a year ago.
Harvey Norman rose 4.4 per cent to a nearly two-year high of $4.95 after the retailer beat expectations with a smaller-than-expected 45.7 per cent dip in pre-tax profit to $283.6 million for the six months to December 31.
Chairman Gerry Harvey told AAP that despite outperforming consensus expectations, he was not that happy with the result.
"They didn't exceed my expectations," he said.
Macquarie Technology Group rose 9.1 per cent to an over two-year high of $77.69 after the data centre company reported its 18th consecutive half-year of earnings growth, a result chairman Peter James said was underpinned by the megatrends in cloud computing and cybersecurity.
The Big Four banks were mixed, with Westpac rising 0.6 per cent to $26.35 and CBA adding 0.4 per cent to $116.41, while ANZ and NAB both dipped 0.1 per cent, to $28.45 and $33.84, respectively.
BHP was basically flat at $43.93 while Fortescue dipped 0.3 per cent to $25.93 and Rio Tinto added 0.3 per cent to $123.78.
The Australian dollar was buying 65.17 US cents, from 65.12 US cents at Wednesday's ASX close.
ON THE ASX:
* The benchmark S&P/ASX200 index finished Thursday up 38.3 points, or 0.5 per cent, to 7,698.7
* The broader All Ordinaries gained 42.4 points, or 0.54 per cent, to 7,959.5.
CURRENCY SNAPSHOT:
One Australian dollar buys:
* 65.17 US cents, from 65.12 US cents at Wednesday's ASX close
* 97.60 Japanese yen, from 98.09 yen
* 60.16 Euro cents, from 60.16 Euro cents
* 51.44 British pence, from 51.44 pence
* 106.78 NZ cents, from 106.71 NZ cents.
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