Tough times mean supermarkets are in a battle to attract shoppers turned bargain hunters with a new bulk buying store opening its doors to challenge American giant Costco.

Locally-owned Grosco opened in Penrith in Sydney’s west two weeks ago, and news of the discount grocery store is spreading fast among cost-conscious shoppers.

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The name has caught attention, with the US-based mega chain Costco spelled with a ‘C’, while the new competitor uses a ‘G’. Both are based in Sydney’s west, offering membership cards and bulk buying options.

“I like to check out, like, okay, if it is cheaper than Costco, then...” one shopper said.

While a Costco membership costs $65, Grosco’s will be $99 from next month. But the grocery prices tell a different story.

Grosco has just opened in Sydney’s west. Credit: 7NEWS

Costco also operates in Sydney’s west. Credit: 7NEWS

A 20kg bag of basmati rice costs $49.99 at Costco but is $13 cheaper in Grosco.

Shoppers can get an extra kilogram of chickpeas for just $1.30 more at Grosco, and bananas are $1.29 cheaper by the kilogram.

“Prices are really very, very reasonable and cheap from other stores because we need in bulk,” Grosco’s Hiral Adhyaru said.

But there is a key difference at Grosco - it’s an Indian grocery store, making their target market much narrower, but hoping to attract customers from all over Sydney.

As shoppers seek more ways to save in challenging economic times, the competition for bargain hunters continues to heat up.