A wave of one-dollar gifts usually arrives overnight. Dozens of them, from names nobody recognizes, many with declined cards mixed in. By morning, someone in development is asking how to make the online donation form refuse anything under ten dollars. It’s a reasonable ask, and the honest answer is that a hard minimum on an Altru donation form is not something you should assume exists. What you can do is shape the form so tiny amounts are rare, and put protections around it so the gifts that do slip through cost you less.
First, figure out which problem you actually have
“We need a minimum donation” usually means one of three different things, and the fix is different for each:
- Card testing. Fraudsters use public donation forms to check whether stolen card numbers work, because a small charge to a nonprofit draws little attention. The tell is a burst of small gifts in a short window, odd or mismatched names and addresses, and a high decline rate. This is a security problem, not a pricing problem.
- Processing fees eating small gifts. A legitimate two-dollar gift can lose a meaningful share to fees, and still generates an acknowledgment, a constituent record, and possibly a batch line to reconcile.
- Gift levels tied to benefits. If a donation at a certain level comes with recognition or a perk, a gift below that level shouldn’t be presented as if it qualifies.
Look at your recent online gifts before you change anything. A revenue query filtered to web donations under your target amount, with transaction date and time, tells you quickly whether you’re dealing with a fraud pattern or just a handful of small, sincere supporters.
What to check in Altru
Altru’s donation web forms let you present suggested gift amounts and decide whether donors can type in their own. Whether your version can enforce a minimum on that open amount field is something to confirm rather than guess. Test it in a sandbox if you have one, or build a test form, enter an amount below your target, and see whether it’s rejected. If you can’t tell, ask Blackbaud support directly: “Can the other-amount field on a donation form enforce a minimum value?” is a clear, answerable question.
If it turns out there is no built-in minimum, you still have real options.
Use preset amounts only
The most dependable way to block small gifts is to remove the open amount field and offer only fixed amounts that start at your floor, such as $25, $50, $100, and $250. The tradeoff is that you lose donors who wanted to give an amount in between. Some organizations accept that on their general donation page and keep a separate, less prominent form with an open amount for tribute or campaign gifts.
Raise the visible anchor
When you keep an open field, the suggested amounts around it do a lot of the work. If the lowest suggestion is $10, people tend to give near $10. If it’s $35, the median gift shifts up. This won’t stop a fraudster, but it changes what ordinary donors choose.
Be careful with custom scripts
You may hear about adding JavaScript to a hosted form to reject amounts under a threshold. Before you go that way, know two things. First, browser-side checks are easy to bypass, so they don’t stop card testing, which is the main reason most teams want a minimum. Second, scripts added to hosted forms can break when the form or page template is updated. If you try it, document exactly what you added and retest after every change.
If the real issue is card testing
A minimum amount alone rarely ends a card-testing attack. Attackers simply test at whatever the minimum is. The measures that matter more:
- Talk to your payment processor. Processors can often apply velocity limits, address and security-code checks, and fraud rules on their side. They see the attack pattern across many merchants and usually have advice ready.
- Ask Blackbaud what bot protection is available for your web forms, such as a CAPTCHA or similar challenge, and turn it on if it is.
- Temporarily take the open-amount form offline during an active attack and send donors to a preset-only form until it stops.
- Clean up afterward. Fraudulent gifts that went through should be refunded, and the junk constituent records they created should be reviewed so they don’t end up on your mailing lists or skew your donor counts.
If the real issue is fees on small gifts
Here a hard floor may be the wrong tool. Small donors are sometimes future members, and turning them away can cost more than the fee. Two softer approaches:
- Offer donors the option to cover the processing fee, so small gifts arrive closer to whole.
- Route very small gifts to a lighter acknowledgment path, such as an automated email receipt instead of a printed letter, so the handling cost matches the gift.
Quick answers
Will a minimum stop fraudulent gifts?
Not by itself. It raises the dollar amount of each test charge but doesn’t prevent the attack. Processor fraud rules and bot protection do more.
Should we refund small legitimate gifts below our new minimum?
Generally no. Thank the donor and accept the gift. Change the form going forward rather than penalizing people who gave before the change.
Where Social Good fits
Everything above can be done with Altru, your processor, and some policy decisions. Some organizations instead move their online giving to Social Good Checkouts, a branded, mobile-friendly checkout for donations, memberships, and tickets that writes the transactions back to Altru and supports options like letting donors cover the card fee. If minimum amounts are a requirement for you, ask us how donation amounts are configured before you decide.
