Cost per acquisition advertising (e.g. TalkLocal, Thumbtack) addresses the risk of CPM and CPC advertising by charging only by the lead. Like CPC, the price per lead can be bid up by demand. Also, like CPC, there are ways in which providers can commit fraud by manufacturing leads or blending one source of lead with another (example: search-driven leads with co-registration leads) to generate higher profits. For such marketers looking to pay only for specific actions/acquisition, there are two options: CPL advertising (or online lead generation) and CPA advertising (also referred to as affiliate marketing). In CPL campaigns, advertisers pay for an interested lead — i.e. the contact information of a person interested in the advertiser's product or service. CPL campaigns are suitable for brand marketers and direct response marketers looking to engage consumers at multiple touchpoints — by building a newsletter list, community site, reward program or member acquisition program. In CPA campaigns, the advertiser typically pays for a completed sale involving a credit card transaction.
Leads may come from various sources or activities, for example, digitally via the Internet, through personal referrals, through telephone calls either by the company or telemarketers, through advertisements, and events. A 2015 study found that 89% of respondents cited email as the most-used channel for generating leads, followed by content marketing, search engine, and finally events. A study from 2014 found that direct traffic, search engines, and web referrals were the three most popular online channels for lead generation, accounting for 93% of leads.