Greggs in Cornmarket reopened this morning but Thames Water is still fixing a leak in the street outside.
The popular bakery closed its city centre branch on July 27 and eventually the chain said the closure was as a result of suspected food hygiene issues.
Fans of the bakery chain's popular sausage rolls were glad the branch was back open.
One shopper said: "I'm from northern Ireland - I'm a big Greggs fan."
Last year the branch - one of the largest Greggs in Europe - closed for two months due to problems caused by a nearby broken sewer.
A Greggs spokeswoman said earlier: "We take all potential food hygiene issues very seriously and took the decision to close our Cornmarket Street, Oxford shop.
"It is expected to reopen on August 15, with extended opening hours so customers can enjoy their Greggs favourites at more times throughout the day."
Greggs has not provided any details regarding the potential food hygiene issues.
Water has been coming up from a drain in the street for several days.
There were celebrations and queues when Greggs opened the branch in March 2020 - the first in the city centre.
It features a spacious seating area upstairs.
It is understood that Greggs in Kidlington has also been closed, while there are plans to expand the Greggs in Headington.
The chain launched its vegan sausage roll in 2019 and it has been popular ever since.
Greggs started in the North East about 80 years ago and now has more than 1,900 branches across the UK.
There are 23,000 staff and the chain is still growing.
This story was written by Andy Ffrench, he joined the team more than 20 years ago and now covers community news across Oxfordshire.
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