A Brief Summary of the Science of Ask Strings

A Brief Summary of the Science of Ask Strings


25 June 2024


By David Allen, Development for Conservation


When I get challenged on the advice I provide in this blog and in various seminars and workshops, it’s usually related to not being able to cite studies and peer-reviewed papers that prove the opinion I espouse.

For the record, I am not writing this blog as a peer-reviewed scientific treatment of fundraising. In fact, most of the time, my point is that you should test these ideas yourself. I am generally dismayed at untested fundraising practices put in place because that’s the way my predecessor did it (single letter appeal requests), that’s the way my one of my Board members prefers to be solicited (single-page letters), or that’s the way we can save paper and money (email appeals and one-size-fits-all landing pages).

For those interested in current behavioral science related to fundraising, I would direct you to DonorVoice and NextAfter, both of which regularly report on fundraising science. They both have blogs which are free to subscribe to,

Yesterday, I re-read a whitepaper produced some years ago by DonorVoice entitled The Science of Ask Strings. I’ll summarize it here, but if you want the full treatment, consider downloading a copy for yourself, complete with citations to the peer-reviewed studies referenced in the paper.


An ASK STRING is a list of options you see enclosed in an appeal letter or on the landing page of a website. A LANDING PAGE is the page to which you are directed when you click on the Donate Now button.

In my view, there are three different places where you might use an ask string: on your website’s main landing page, on specialty landing pages used for campaigns and appeals, and in fundraising letters.

There will be a tension between raising money and generating responses. In general, asking for more money will help you raise more money, while asking for less money will generate more responses.

Let’s consider first the general landing page of your organizational website. We should assume that people finding that page are people who do not already give to the land trust, or at least have been lapsed for a while. (If they were current, you would be sending them to a different landing page.)

So, you might think about making it super easy to give. Explain that donations of every size are needed and useful in accomplishing the mission. Suggest that many people give $50 (or $35, or ??).

That’s called an ANCHOR.

Then perhaps provide a testimonial from someone who gives at that level.

This is called SOCIAL PROOF.

And then offer just one or two options for giving.

_____$35          _____Other

In one NextAfter experiment, eliminating the ask string altogether, and simply letting the potential donor choose, was tested against controls. The results were unexpected and significant with conversion increasing from 0.10% to 0.14%.


In almost every case, when you are asking people who already give to give again, you will NOT want to send them to the general landing page. Instead, you will want to create special landing pages for them.

Perhaps one starting at $35 with four options:

____$35    ____$50    ____$100    ____Other

Or one starting at $100:

____$100    ____$250    ____$365    ____Other


You might need 5 or 6 landing pages before you’re done. Then each gets its own QR code for paper letters and hotlink for email.


To further understand ask string science, we need to now offer up a few definitions:

An ANCHOR is an ask amount that you explicitly request in your solicitation message. Asking for a specific amount – offering an anchor – will always help you raise more money.

Anchors for renewals and appeals to current donors are usually related to the donor’s giving history. Common options are the Highest Previous Contribution (HPC), Most Recent Contribution (MRC), and Average Contribution (AC).


Most organizations tend to use the Highest Previous Contribution. Testing suggests that this might be a good way to raise more money – at the expense of the response rate. But for lapsed members – where the object is to get as many as possible to respond – use the Most Recent Contribution.

And for renewals use the Average Contribution. (Not a forever average – I would use a 5-year-average.)

However, the Anchor amount does not necessarily need to be the MRC, or AC. You could ask in the letter or email for a gift somewhat larger that their MRC or AC. I have done well with ask strings that start with their MRC and then include the Anchor value in the second position.


For example, if their Most Recent Contribution was $50, I might use the letter to ask for $100 and use this ask string:

____$50    ____$100    ____$250    ____Other

And if their Most Recent Contribution was $250, I might use the letter to ask for $365 and use this ask string

____$250    ____$365    ____$500    ____Other


I also hedge my bets by sending a follow-up letter several weeks later to those who don’t respond that uses their MRC as the Anchor – and uses the exact same ask string.


Challenging donors to give more is important primarily because there is good evidence that a donor making the same level gift three years in a row will have psychological difficulty responding to a request to give more. They will need a good reason – like a yummy project appeal – to break that giving pattern. Conversely, asking someone who just increased their gift last year to do so again this year (within reason, of course) is more likely to accept the increase.


As you begin to lay in plans for Fall fundraising, I hope that this primer will be helpful. I’d love to hear about your experience. What are you testing? What seems to be working for you?


Cheers, and have a great week!




PS: Your comments on these posts are welcomed and warmly requested. If you have not posted a comment before, or if you are using a new email address, please know that there may be a delay in seeing your posted comment. That’s my SPAM defense at work. I approve all comments as soon as I am able during the day.


Photo by Jarko courtesy Pixabay



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  • Emily Torres Barton
    Posted at 15:15h, 26 June Reply

    Thanks for this blog topic, David! How frequently do you attempt to move donors up a level if your evidence shows that giving 3 times at the same level makes their behavior physiologically “sticky”?

    • David Allen
      Posted at 16:12h, 26 June Reply

      Great question, and I’m grateful that you asked. I don’t think there’s a formulaic answer to it, unfortunately. I would ask for what they gave last year and then show them an ask string that includes several levels higher. Some will jump to higher levels anyway, but it might be related to factors you can’t see, like some windfall they received, or turning 72 and a half and facing RMDs for the first time. Meanwhile look for a reason to ask for more. People giving $100 each year might give $500 in support of a specific project, or to build organizational capacity to add a stewardship position. At that point, their Most Recent Contribution is $500.

      Good to hear from you! -da

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