For merchants, services can include providing tracking technology, reporting tools, payment processing, and access to a large base of publishers. For affiliates, services can include providing one-click application to new merchants, reporting tools, and payment aggregation. The networks are free to join for affiliates. The merchant on the other hand has to pay a fee. Traditional affiliate networks might charge an initial setup fees and/or a recurring maintenance fees. This differs from network to network. It is common for affiliate networks to charge merchants a percentage of the commission paid to the affiliates as fee for their services.
Traditional affiliate networks allow the merchant to offer its publishers revenue share or cost per action as compensation method. The majority of merchant programs prefer revenue share over cost per action.
CPA networks take advantage of the ability to get higher commission rates due to their high volume, which they pass in part down to their affiliates. Average affiliates usually get paid a lower commission if they promote the merchant directly, because they are rarely able to generate the required volume to reach the higher payout tiers.