Discount designer website, the spin-off of luxury etailer Net-a-Porter, crashed in some markets on Friday when it hosted a “pop-up Sale” to celebrate its first birthday, selling designer items for just £1.

Separate Sales were held on the UK site and the US site – where products sold for $1 each.

All of the £1 and $1 items sold out within hours, making it the fastest Sale event on the site since its launch in April 2009.

Products were limited to one per person. However, some shoppers were left disappointed as the volume of traffic to the site meant it crashed in some markets.

Stephanie Phair, director of theOutnet, said: “This remarkable volume – up to nine orders a second – led the site to crash in some markets and I want to say that we are very sorry to all those disappointed people who didn’t get to buy anything at the Sale, but delighted for all of those who did.”

She added: “Thousands of happy Outnet customers walked away with once-in-a-lifetime bargains for £1 or $1. We want to thank everyone for being part of our first year celebrations and with each event we are working hard to fix issues that arise so we can serve you better and continue to offer amazing bargain shopping opportunities.”

Net-a-Porter was acquired by Swiss luxury goods group Richemont at the beginning of this month.