Cookie Duration

What Is Cookie Duration?

Cookie duration (or lookback period) is the timeframe a tracking cookie persists on a user's browser after clicking an affiliate link. If a user clicks an affiliate link and a 30-day cookie is set, any purchase within 30 days is credited to that affiliate; a purchase on day 31 is not.

Cookies store information in the user's browser, enabling attribution across multiple sessions. Users might click an affiliate link, browse your site, leave, return a week later, and complete the purchase. The persistent cookie still attributes that sale to the affiliate.

Cookie duration balances fairness to affiliates (longer cookies benefit partners) against fraud prevention and accuracy (shorter cookies reduce attribution inflation).

Typical Cookie Durations

Standard durations range from 7 days to 90 days, and typical settings vary by market:

• B2B SaaS, where sales cycles run longer: 30-60 days, with 30 days the industry standard
• Consumer products and e-commerce: 7-30 days
• Generous programs designed to attract and retain partners: 60-90 days

Some high-end affiliate programs offer tiered cookie durations: 30 days for standard partners and 60 days for top performers. This creates an incentive to reach higher performance tiers while protecting against fraud risk.

Cookie Duration Impact on Affiliate Performance

Longer cookie durations increase affiliate earnings and motivation. A 7-day cookie might credit only 30% of eventual conversions, while a 30-day cookie might credit 60-70%. This 2x difference in credited conversions directly impacts affiliate compensation.

Partners negotiating cookie durations often push for 30+ days. Programs with generous durations attract and retain partners because earnings potential is higher. Restrictive durations (7 days) frustrate partners, who drive traffic but lose credit for conversions beyond a week.

Cookie duration also reflects trust. Longer durations signal that the company trusts partners and customers and believes in product quality, while short durations signal concerns about attribution accuracy or fraud. Partners perceive cookie policies as a program quality signal.

Technical Cookie Implementation

Cookies are small text files set by affiliate tracking domains when users click links. A typical format looks like: visitor_id=abc123; path=/; expires=30d; domain=affiliate-tracker.com.

First-party cookies (set on your domain) persist better than third-party cookies (set on affiliate domains) because browsers increasingly block third parties for privacy. Modern tracking often uses first-party cookies set when users reach your domain via affiliate links.

Cookie duration is specified as an expiration date: 30 days from click, 90 days from click, and so on. Platforms implementing tracking should clearly document cookie duration in their terms of service and privacy policies.

Where Cookie Tracking Breaks Down

Several factors erode cookie-based attribution:

• Users can manually delete cookies, and some browsers auto-delete cookies between sessions
• Privacy-focused browsers block third-party cookies entirely, reducing cookie effectiveness
• Cookie consent regulations (GDPR in the EU, CCPA in California) require explicit consent for tracking cookies
• Native mobile apps do not use browser cookies, so they require SDK-based tracking
• Progressive deprecation of third-party cookie support is pushing the industry toward first-party cookies and alternative tracking

When cookie-based tracking fails, some affiliates use cookieless alternatives such as server-to-server pixel fires and email domain matching.

Cookie Duration and Compliance

GDPR limits cookie duration and requires explicit consent before tracking. The default GDPR cookie duration is 13 months for analytics, but affiliate tracking falls under advertising cookies, which are subject to stricter requirements. CCPA provides similar restrictions.

Affiliate programs in regulated jurisdictions must adjust cookie durations to comply, often limiting to a 30-day maximum in EU markets. Transparency requirements mandate that affiliates and companies disclose cookie tracking in privacy policies, and non-compliant practices trigger regulatory penalties and reputational damage.

Best practices:

• Obtain explicit user consent before setting tracking cookies
• Use first-party cookies where possible to improve compliance
• Set reasonable durations, with 30 days as the standard
• Provide clear cookie policies

Affiliate programs operating internationally should implement jurisdiction-specific cookie duration policies, and affiliate platforms typically provide compliance-ready cookie implementation. Partners should understand cookie duration policies and confirm compliance with regulations in their operating regions. Cookie regulations continue evolving, so staying current with changes is essential for compliant affiliate programs.