Which comes first?
[ ] Bank the check
[ ] Thank the donor
[ ] Update the database
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Answer: Thank the donor[1]
Notes and assumptions....
Thanking has nothing to do with courtesy, from a business point of view.
Thanking is simply the first — and by far most important step — you can take to establish a longer-lasting and positive relationship with fundraising's customer, i.e., the donor.
A new donor will judge you first by the quality and speed of your thanks — as many, many bits of very good research confirm.
A deeply felt, fast thanks is just good customer (i.e., donor) service.
When you deal with customer service first and foremost you will reap extraordinary rewards. Promise.
If you want to reap ordinary returns, bank the check first. Or update the database. Either one. Doesn't matter. Both are wrong.