Online Donation, Volunteer and Charity Concept. Woman Making Donate via Internet on Mobile Phone. Closeup 2023/08/AdobeStock_387525393-1-e1694547997424.jpeg

Defaults and Donations

Understanding Donor Behaviour and Online Donations

When there is an urgent need for funds, what are the best practices to prompt generosity? FOS Co-Director Raji Jayaraman’s research partnership with is helping to inform those best practices.

Online donation platforms, like, are transparent, secure, and convenient tools for charitable donors. The platforms also relieve charities and NGOs of needing to build and maintain their own online donation infrastructure so they can focus on their core responsibilities and missions. and other donation platforms are also responsible for soliciting co-donations, often referred to as tips, from donors to fund their own operations and development.

On, as soon as would-be donors click the “donate” button, they are presented with a form that includes two suggested donation amounts. One amount recommends the size of their gift to the cause, and the other is to support the platform and its operations. Those recommended amounts are called defaults, and donors can increase or decrease the amount as they choose. Does the default amount play a role in determining how much donors give after seeing it?

In an experiment, Jayaraman’s team randomly assigned default donations of 10, 20, or 50 Euro each time the donation form was opened. A control group of’s potential donors was randomly assigned a default amount of 0.

Over the 11-month-long experimental period, there were about 680,000 visits to the donation page. These visits resulted in 23,000 donations. While only about 3.33% of page visits resulted in a donation, the total value of those donations was 1.17 million Euros. The visits that resulted in donations to the charities yielded 45,500 Euros in co-donations, or tips, to fund the platform itself.

“We implemented AB testing based on the process Raji developed with us and were, therefore, able to base our product decision on a scientific approach instead of assumptions.”

Eva Schreyer, Lead Data Analyst,

After analyzing data captured from page visits to, Jayaraman and her team could compare the donation and tip amounts to the default amount prompts the donors saw.

The results show that donors generally follow the platform’s default donation amount.

  • More than 20% of donors shown the 10-Euro default amount went on to donate 10 Euros. In contrast, only 12% to 14% of donors gave 10 Euro once they were shown a default of 20 or 50 Euros.
  • Overall, seeing any default amount makes donors 30% to 90% more likely to donate the first amount they are displayed. The rate of compliance drops as the default amount rises.

The paper describing the experiment conducted by FOS Co-Director Jayaraman and her team with is published in The Review of Economics and Statistics (2019). and Jayaraman continue collaborating on experiments that generate evidence for decision-making and defining best practices moving forward.

“Before we went into the first project with Raji our decisions were based on assumptions and educated guesses, but with her help we were able to determine what is actually best for our business in terms of revenue.”

Eva Schreyer, Lead Data Analyst,