TopCashBack and Quidco pay registered users to buy items via their sites rather than directly from retailers' online stores.
TopCashBack, which has previously invested in digital and outdoor advertising, is to launch a six-figure TV campaign next month. The ad, created by Fresh, depicts a family saving money on its shopping by using its service.
Using the strapline 'The UK's number one cashback site,' the ad is intended to raise the profile of the website and highlight the fact that the service is free to use.
The ad will also promote the promise to match other cashback sites' incentives through its 'highest cashback guarantee', as well as strengthen the company's brand positioning as 'the most generous' cashback site in the UK.
TopCashBack, which feat-ures deals from brands including Tesco, O2, RAC and Argos, positions itself as the only cashback site that does not charge administration fees to users.
Launched in 2005, TopCashBack also claims to have nearly 1m registered users in the UK and receive 70,000 page impressions a day.
Rival website Quidco, meanwhile, plans to roll out a multimillion-pound integrated marketing campaign in the next few weeks, including its first TV ads.
The campaign, created by Addiction, will also feature print and radio ads.
Quidco, which is also to launch a series of iPhone apps, claims to have 1.2m members in the UK and offers deals from about 2000 retailers, such as Dixons, Vodafone and PizzaExpress.
According to Nielsen, Quidco's above-the-line adspend was £30,000 between March 2010 and February 2011.