The underpass had been used by 700,000 shoppers a month, but it was forced to close in October 2006 because of the construction of Ion Orchard.
Ever since the closure, Wisma Atria's footfall has suffered, with retailers reporting up to a 40 per cent slip in business.
'We have been working closely with our business partners and the related authorities these past two years, and are heartened by the timely reopening of the linkway,' said Mr Franklin Heng, chief executive of YTL Pacific Star, which manages Starhill Global.
Traffic to the Wisma Atria basement has more than doubled over the five-day period up to Sunday, following the reopening of the linkway last Wednesday.
Pedestrian traffic is expected to further increase when escalators leading from the Orchard MRT station to street level are commissioned later this year.
A new side entrance at Wisma Atria level 2 will also serve commuters exiting the MRT station.
The reopening of the underpass coincided with the start of the Great Singapore Sale and comes at a welcome time for retailers, given that visitor arrivals to Singapore in April fell 6.1 per cent to 780,000 compared with the same month last year.
Starhill Global, formerly known as Macquarie Meag Prime Reit, owns 74.23 per cent of Wisma Atria. Its units fell 2.5 cents to close at 70.5 cents yesterday. While values have recovered since lows of 38.5 cents this March, they are a distance from the high seen in May 2007.

