Previously, buy.at handled the Asda account as a secondary network to performance-based digital marketing company TradeDoubler.
Asda's affiliate marketing activity is designed to increase sales at asda.co.uk covering electricals, books, DVDs, mobile phones, clothes and groceries.
Sales will be tracked and analysed through buy.at's management area, with variable commissions paid to the affiliates for each sale.
Chris Dalrymple, Asda online marketing manager, said the company was keen to review its account and to carry out test activity before consolidating into one affiliate network.