The Giving Tuesday send that tanked a nonprofit’s domain reputation

Before Giving Tuesday, leadership often asks email teams the same question: “Why aren’t we emailing everyone?”

Last year, a tech advocacy nonprofit sent its Giving Tuesday appeal to its full list, and Gmail rejected most of the messages sent to its users. 

The big problem started months earlier, when the nonprofit moved its newsletter to a new platform.

With help from MV Braverman, founder of the deliverability consultancy Inbox Welcome, the team got its year-end emails back into inboxes. 

Case study: A newsletter move with a hidden cost
Early in 2025, the nonprofit moved its newsletter to Substack, which took over regular sends to its list of about 181,000 people. 

Fundraising stayed in HubSpot, along with smaller emails to donors and event attendees.

Inbox providers judge senders partly by their domain’s recent sending history, and Substack sends from its own domain. 

Those big sends built Substack’s history, while the nonprofit’s domain, used only for small HubSpot emails, went cold.

The Giving Tuesday HubSpot appeal to all 181,000 supporters was the domain’s first big send in more than nine months. 

Many of those contacts hadn’t engaged in ages, and they got a fundraising ask in place of the usual newsletter.

HubSpot showed nearly every email as delivered, but only 3.4% of recipients opened the appeal. 

“Delivered” only means the receiving server responded, so it can’t tell you whether anything reached an inbox.

Google’s free sender dashboard, Postmaster Tools, painted a much uglier picture. 

Gmail had rejected 57% of the messages sent to Gmail addresses as suspected spam and dropped its trust rating for the domain from High to Low (a rating Google has since retired).

The fix: Earn trust back before asking for money
With pressure to email everyone again for year-end, MV’s first directive was a tough sell: stop full-list HubSpot sends before they did lasting damage.

Instead, the team pulled about 9,300 recent donors and openers likely to recognize the sender.

Before any ask, that group got one email built around a spokesperson’s recent appearance on a hugely popular podcast.

It went out in seven batches over three days to avoid another volume spike.

Opens climbed from about 14% to about 30% across the batches, giving the domain a fresh track record with Gmail.

The year-end HubSpot appeals then went to that same group on December 29 and 31.

For everyone else, MV pushed for a fundraising appeal on Substack, which the team saw as strictly editorial. 

But they tried it. Since Substack sends from its own domain, the appeal reached the full list without risking the nonprofit’s domain.

The results
Gmail stopped rejecting the emails after Giving Tuesday, and the domain’s trust rating was back to High by mid-January. The recovery held.

The year-end HubSpot appeals averaged a 28% open rate, up from 3.4% on Giving Tuesday. Part of that came from emailing more engaged supporters instead of the entire list.

Gifts couldn’t be tied to specific emails, but one-time website gifts from December 28 to 31 came in an estimated $19,000 to $22,000 above normal daily giving.

How to avoid a Giving Tuesday crash
Check your recent sending history. If an appeal will dwarf recent sends, start with your most engaged supporters.

Send consistently, no matter the platform. Steady sends keep each domain from going cold between big appeals.

Give people a reason to open first. Timely content with no ask builds trust before the appeal lands — the kind of emails you want to send in the lead-up to Giving Tuesday and year-end.

Look past your platform’s delivery rate. Postmaster Tools shows how Gmail is actually treating your email.

The bottom line
Using different platforms for different emails works fine until one of your domains goes quiet. 

Before your next big moment, be sure you know which domain each platform sends from.

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‘Til next time!
Sara