Fundraisers know the value of thanking donors for their gifts. The pressures of time and lack of certainty about results can crimp efforts to express appreciation.

During the 2014 International Fundraising Congress (IFC), Geoffrey W. Peters, chairman of CDR Fundraising Group, shared the findings of his organization with a test it undertook.

The test involved 6,225 total donors, who had given between $50 and $249.99, one time or as multiple donors. They had given one gift to a disaster appeal within the previous year. Of that, 2,131 received no acknowledgment, just ongoing mail, 2,094 received a thank-you telephone call, and 2,000 received a thank-you note.

Peters shared the results of the findings from the test:

• Thank-you calls increase subsequent giving. The subsequent gift rate for donors who received a call was 47 percent higher than those who received no thank-you response and 22 percent higher than those who received a thank-you note.
• The thank-you call increased the average size of the subsequent gifts. The average gift from donors who called was 8.3 percent higher than those who received no acknowledgment and 3.5 percent higher than those who received the note.

The donors who received the phone call generated an additional $8,661 in gross revenue at a 2.4:1 return on investment (ROI).