Kiwis shoppers are paying up to three times as much as their Australian counterparts when buying electronic goods and homeware online.
The Herald on Sunday found a number of items were significantly cheaper when bought from sites in Australia compared with New Zealand websites - even in cases where the company selling them was the same.
Items on the Australian sites could not be shipped to New Zealand.
Consumer New Zealand said it was not uncommon to find "huge price differences" when comparing prices on goods sold here with overseas charge, either in Australia or other parts of the world.
Higher GST rates, a smaller market and high transportation costs accounted for some but not all of the difference, researcher Jessica Wilson said.
"For some goods, Kiwi consumers are paying a premium."
A price comparison by the Herald found Beats wireless headphones were listed online at NZ$599 for JB HiFi's Kiwi customers, while those ordering from the company's Australian online shop could snap up the exact same pair after currency adjustments for NZ$327 - nearly half the price.
A Canon DSLR camera was NZ$799 on the New Zealand website while its Aussie counterpart was at NZ$533 about a third cheaper.
A Panasonic microwave oven was also close to a third cheaper on the Australian website, as was a set of salt and pepper grinders.
And on Harvey Norman's online Australian store, a pair of Sennheiser wireless headphones were NZ$543, $257 cheaper than on the New Zealand website where they were listed for NZ$799.95.
A Vidal Sassoon hair dryer advertised as a "huge deal!" for NZ$146 online for Kiwi shoppers was NZ$42 cheaper in Australia.
Similarly, a Breville electric kettle was NZ$58 cheaper at NZ$141 in Australia than on the Kiwi version of the website.
JB HiFi's general buying manager Rod Korff said the company acknowledged the differences, a result of several factors.
"Including, amongst other things, freight costs and differences in the respective countries tax (GST) rates.
"JB Hi-Fi New Zealand source a large proportion of product through the local New Zealand distributors or suppliers branches and we work closely with those suppliers to provide Kiwis with the best value we can."
Korff said in the case of the salt and pepper shakers, the company had been able to negotiate special pricing in New Zealand and had offered the set at similar prices to Australia in the past.
Harvey Norman spokeswoman Kerry Maconaghie said the company "doesn't wish to make any comment" about the price differences.
Pricing on both the Australian and New Zealand online KMart stores bucked the trend - no significant price difference were seen on items we checked and in several cases speakers we compared were the same price, meaning they were actually cheaper in New Zealand once currency adjustments had been made.
Many Australian websites won't ship direct to New Zealand, but standard postage across the Tasman for a package up to 20kg costs less than NZD$20 with Australia Post.
Kiwis determined to get a bargain could enlist a friend to have an item delivered to their Australian address, then have them send it on from the local post office.
Last year, Kiwis living in Australia said they were shocked to see how much more groceries cost back home - at the time, kumara was selling in New Zealand for $8.29 a kilo, compared to AUS$.79 in Aussie supermarkets.
And earlier this month the question of price was raised again when it was discovered avocados were a fraction of the price across the Tasman.