Impact of Donations

2015 Impact of Donations - Shelter Comparison

Based on data from our December 2015 recommendation process.

For more recent thoughts on sanctuaries, including their values and how to maximize their impact, see our blog entry from September 24, 2015.

Some animal charities can help many more animals than others with your donation. Much of this difference is due to the differences in efficiency between different ways of helping animals. We explored this difference by comparing the effects of a $1000 donation to a companion animal shelter or to an ACE top charity, resulting in the chart above. Although there is some variation in the effectiveness of different charities and we have some uncertainty about the outcome of particular programs, by donating to an ACE recommended charity you can help many more animals than you would by donating to a conventional shelter.

About the Data

  • Estimates for costs to animal shelters were obtained by searching Google for “what does it cost for an animal shelter to rescue a cat or dog” and visiting the resulting shelter/SPCA/humane society (but not sanctuary) websites. If the shelter provided its own estimate of what it cost, on average, to place an animal, that estimate was recorded. If the shelter provided its budget and an approximate or actual number of animals served, those were recorded and used to produce an estimate. If we could not find enough information on the shelter website to make an estimate, nothing was recorded. Some shelters provided enough information to make both kinds of estimates, in which case both were recorded. A total of 10 estimates were obtained. Average costs were also weighted by the number of animals served by the shelter to produce a weighted mean estimate.
  • Estimates for costs to save lives through recommended charities were produced as follows:
    • For all top charities, we estimated the number of lives spared per $1000 donation during the review process. More information about how we created those estimates is available on the Animal Equality, Mercy For Animals, and The Humane League full review pages. This was the starting point for our estimates of effectiveness used here.
    • We then estimated the effectiveness of each group’s work in more detail by using the three columns in the Leafleting and Online Ad Impact Calculators to provide upper and lower bounds for the effectiveness of various activities. We created estimated probability distributions for the total number of lives saved by a $1000 donation to each organization using these estimates.
    • We then created a final distribution by combining the distributions generated in the previous stage, weighting each equally. A smoothed version of this distribution is shown in the plot above.
    • We created a single “best guess” estimate by taking the median number of lives spared according to the estimates above.

About the plot

  • For each group of charities, estimates were plotted using a violin plot on a log scale. The tails of the violin plots were trimmed to the range of the data.
  • For the animal shelter group, the weighted mean estimate was superimposed on the violin plot.
  • For the recommended charities group, the “best guess” was superimposed on the violin plot.


ACE. Animal Equality Review. December 2015.
ACE. Leafleting Impact Calculator.
ACE. Mercy For Animals Review. December 2015.
ACE. Online Ads Impact Calculator.
ACE. Recommended Charities Estimated Impacts with Error Bounds.
ACE. The Humane League Review. December 2015.