The store is trading under the fascia Family Bargains, which has been trialled since June this year and frees the retailer from its fixed price point.
Trial stores, at Fareham, Banbury and Carmarthen, had proved popular with shoppers and would now be rolled out to further sites, said commercial director Hussein Lalani.
The Bristol store is a former Woolworths site and has the strapline Big Brands, Small Prices. Prices range from just 49p to more than £49.99.
"These are very exciting times on the high street with shoppers no longer prepared to pay over the odds for everyday essentials like washing up liquid, coffee and toothpaste," Lalani said. "Having sampled smaller priced bargains, as they have at 99p Stores, Britons have now developed a taste for higher value bargains."