Australians will be looking to spice up their image as they splash cash during Afterpay Day, but money experts have warned them to show restraint.

The sale kicks off today and runs through to Sunday, with Afterpay revealing that fashion and beauty are the most popular categories the buy now, pay later service is used for.

Consumers are also likely to spend $150 on average, according to Afterpay.

"Shoppers can now enjoy all the deals they've come to love across a massive four-day period both instore and online," EVP of Sale ANZ and Global Instore at Afterpay, Rachel Kelly, said.

But they've been urged to not break their budgets

"Financial counsellors are seeing more and more people with buy now, pay later debts and we're really worried about that because it's really easy to get in over your head, because the requirements on them to assess affordability are just not adequate," Financial Counselling Australia CEO, Fiona Guthrie, said.

Afterpay requires users to make the first payment upfront, and while the BNPL provider reserves the right to conduct a credit check but users won't necessarily face one.

"Buy now pay later providers tell you it's about better budgeting, but it's not that at all, it can make it much harder to manage your money," Ms Guthrie said.

"People end up with debts across multiple providers, all with different timings on when they need to be paid."

Ms Guthrie said of particular concern were consumers in tight financial positions who paid down their buy now, pay later debts on their credit cards.

"When that happens, you might end up not being able to pay down your credit card," she said.

Financial comparison website Canstar's group executive of financial services, Steve Mickenbecker, said he encouraged shoppers to connect their Afterpay account to their debit card.

"That at least implies you have the money there and it's not going onto debt that might linger for a long time," Mr Mickenbecker said.

He said BNPL payments should only be made on credit if the consumer knew they could pay off the debt on their card at the end of the month.

A recent Canstar survey of more than 2000 Australians aged 18 and over found almost half of respondents would consider using BNPL to service a purchase.

Electronics was the most popular category they would consider using it for, followed by furniture, appliances, clothing and homewares.

Forty per cent of respondents who said they would consider using BNPL said they would do so to avoid paying interest on purchases, while 36 per cent said it would help with cash flow management and budgeting.

Of those who said they would not use BNPL, almost half said they would not purchase something unless they had the money to pay for it upfront.

AFTERPAY DAY DEALS

FASHION

Country Road: further 20% off reduced items

Kristin Ash: use code 20FORYOU at checkout

P.E. Nation: up to 40% off

I.AM.GIA: up to 70% off selected styles

Urban Outfitters: 15% off

Tigerlily: 20% off full priced items over $100

Bally: 20% off with code APMAR2021

Kate Spade: up to 50% off select styles

Coach: up to 50% off select styles

Shona Joy: 20% off selected styles

Lee Matthews: extra 20% off with code EXTRA 20

Lacoste: 25% off full priced styles with code AFTERPAY

Furla: Up to 50% off selected styles

BEAUTY

Adore Beauty: 20% off selected brands

Evo Hair: 15% off sitewide

MAC Cosmetics: 15% off all products

Skin Republic: spend $75 and save 30% off

YSL Beauty: spend $50 to save 15% with code AFTERPAY

Lancome Australia: purchase two products to receive the third free

HOMEWARES/TECH

Adairs: up to 30% off

Sheridan: up to 30% off

Mocka: up to 25% off selected products

Freedom: up to 25% off sofas and furniture

Samsung: up to 20% off with code AFTERPAY

Dyson: up to 30% off

Originally published as Shoppers warned over Afterpay Day sales