Two major airlines have also added to the December 26 bargain hunt early on, announcing hundreds of thousands of discounted flights.
The total spend on Boxing Day sales this year is expected to surpass $3.1 billion.
One in three Australians, equivalent to more than seven million, plan to shop the sales in 2025, according to comparison website Finder.
Tracking prices ahead of time made it easier to spot real discounts, money expert Rebecca Pike said.
"Signing up to retailer mailing lists can also pay off, with early access and subscriber-only offers often released before the public sales go live," she said.
Tracking allows customers to identify when a retailer has marked up items before a sale or compare discounts against recommended, not actual, prices.
Shoppers should always compare final prices across different stores to ensure they are getting the best value.
To get more bang for their buck, stacking discounts with cashback offers, loyalty points, coupon codes or credit card rewards can also pay off, Finder said.
On Friday morning, Qantas announced one million discounted fares across more than 100 domestic routes around Australia from $109 one-way, while Virgin Australia is offering more than half-a-million fares starting from $49 one-way.
The Qantas sale runs for 72 hours until December 28, while the Virgin flights are on sale until December 29.
Research released on Friday by digital payment platform Paypal says Australians are taking a practical approach to the Boxing Day sales, with 30 per cent of shoppers polled planning to use the event to stock up on groceries and everyday essentials.
Nearly one in three said they were taking a "buy better, not more" approach to sales shopping and 24 per cent said they would be more cautious about what they buy.
"Australians are becoming far more intentional about how and when they spend, particularly as cost-of-living pressures continue," PayPal spokesperson Danielle Grant said.
"Boxing Day is ... a chance to plan ahead, prioritise essentials and make smarter decisions with their money as they close out the year."
Finder said customers should read retailer policies before buying, with many Boxing Day purchases coming with tighter conditions, including shorter refund windows or no-return caveats.
Ms Pike urged shoppers to avoid getting sucked into buying things they don't need just because they looked like a good deal.
"Stick to a list and have a strict budget in place," she said.
But as they rush to secure the best bargains, shoppers should also prepare for an influx of scams as bad actors hunt for a post-Christmas payday.
Australians have lost about $40 million to buying and selling scams over the past year, with almost two-thirds having experienced a shopping scam, according to research from the Australian Banking Association.
Fake order confirmations, in which people get a notification about an order they never placed and are asked to click a link, are the most common type of ruse.
Social media shopping scams in which sellers vanish after payment are also frequent.
Scammers were evolving their tactics with artificial intelligence to mirror legitimate businesses to rope in more victims, banking association boss Simon Birmingham said.
"Double-check you're purchasing from a legitimate website and watch out for text messages about missed deliveries, as this is a common way for scammers to get you to hand over personal or financial details," he said.
20°C