Every fall, someone pulling the year-end mail file runs into the same question: how far back do we go?
Donors who gave in the last 12 months are easy. They get the appeal. But what about the person who gave two years ago? Or four? Some organizations mail everyone who has ever given, because “you never know.” Others cut off at 24 months because that’s what they did last year and nobody remembers why.
Neither is a decision. It’s a habit. And when you’re paying for printing and postage on every name, the cutoff for lapsed donors in your year-end appeal is one of the few choices in the campaign you can actually work out with arithmetic.
Your lapsed file is bigger than you think
Start with why this matters. The Fundraising Effectiveness Project’s Q4 2025 retention data put overall donor retention at 43.3%. Put another way, more than half the people who gave in 2024 didn’t give again in 2025.
That happens every year, so lapsed donors pile up. For many small and midsize nonprofits, the number of people who have given at some point but not recently is larger than the active file. That’s a lot of names to either mail, email, or quietly ignore.
It’s also a group with a real advantage over strangers. These people already chose you once. Many of them didn’t leave because they were unhappy. They drifted, got busy, or never heard enough from you to give again. (If you want to dig into why, Why Your Donors Stopped Giving covers the most common reasons.) Year-end, when giving is already on their minds, is one of the best moments to invite them back.
But “they might come back” doesn’t tell you how many to mail.
Recency matters more than history
The most useful way to sort lapsed donors is by how long it’s been since their last gift. Response usually drops as the time since the last gift grows. A donor who gave 14 months ago still remembers you. A donor who gave six years ago may have moved, changed priorities, or forgotten your name.
So split your lapsed donors into bands:
- 13 to 24 months since last gift
- 25 to 36 months
- 37 to 60 months
- More than 60 months
Then look at what each band did in last year’s year-end appeal: how many were mailed, how many gave, and the average gift. If your database can’t tell you that, it’s worth an hour with your gift report this week, because it turns this whole conversation from opinion into evidence.
One caution. A large lifetime giver who lapsed three years ago is a different case from a $25 donor who lapsed three years ago. Pull your former larger donors out of the band analysis entirely. They deserve a personal note or a call, not a spreadsheet decision.
The break-even math
Here’s the calculation. For any segment, the break-even response rate is your cost per piece divided by your expected average gift.
Imagine a literacy program, call it the Riverside Literacy Project, mailing its year-end appeal at about $0.85 per piece, all in. Using last year’s results, it estimates each lapsed band:
| Segment | Names | Response rate | Avg. gift | Revenue | Mail cost | Net |
|---|---|---|---|---|---|---|
| 13 to 24 months | 600 | 4.0% | $60 | $1,440 | $510 | $930 |
| 25 to 36 months | 500 | 2.0% | $55 | $550 | $425 | $125 |
| 37 to 60 months | 1,000 | 0.8% | $50 | $400 | $850 | -$450 |
These are hypothetical numbers for illustration, not benchmarks. Use your own.
The break-even rate for the 25 to 36 month band is $0.85 divided by $55, or about 1.55%. At 2%, that band clears it, barely. The 37 to 60 month band needs about 1.7% to break even and is running at 0.8%, so it loses money on the first gift.
The 13 to 24 month band is the clear win. If your organization isn’t mailing those donors at year-end, start there.
When losing money on a segment is still a good decision
Here’s where I’d slow down before cutting the older band. Losing $450 on 1,000 names sounds bad. But that mailing brought back 8 donors, which works out to about $56 per reactivated donor.
Compare that to what it costs you to acquire a brand-new donor. If you’re spending more than $56 to find a new one through acquisition mail or digital ads, those 8 reactivated donors are a bargain. If you’d like to put a number on your own acquisition cost, How Much Can You Afford to Pay for a New Online Donor? walks through it.
The deciding question isn’t “Did this segment net money in December?” It’s “Is this the cheapest way available to us to get a donor back on the active file?” Sometimes the answer is yes, even at a loss. Sometimes your budget simply can’t absorb it this year, and that’s a legitimate answer too. The point is to make the choice on purpose.
A practical rule: mail every band that breaks even. For bands that don’t, mail them only if the cost per reactivated donor is lower than your acquisition cost and you have the cash to wait for the return.
Email changes the math for older donors
Email costs almost nothing per message, so the cutoff doesn’t apply the same way. If you have working email addresses for donors who lapsed five or ten years ago, include them in your year-end email series even if you drop them from the mail file.
The one thing to watch is deliverability. Very old addresses that haven’t opened anything in years can drag down inbox placement for everyone else. If an address hasn’t opened in a long time, a short re-permission or “are you still interested?” email before December is safer than dropping it straight into your biggest sends.
Don’t send lapsed donors the same letter
Including lapsed donors is half the decision. The other half is what they read.
Your active donor letter probably assumes a recent relationship: “Thank you for standing with us this year.” To a donor whose last gift was in 2022, that line rings false. A simple personalized opening works better: acknowledge the last gift, tell them what it helped do, and invite them back.
There’s some evidence for this. NextAfter ran a year-end email test with the Missionary Oblates of Mary Immaculate, sending donors who hadn’t given in at least five years either standard copy or the same copy with their last gift date and amount added. Conversion went from 0.36% to 1.2%, more than triple. That’s one test with one organization, so treat it as a strong hint rather than a law. But it’s cheap to try, and in mail it’s usually a single variable field.
Here’s sample language for a lapsed version, using the same hypothetical literacy program:
“Your last gift to the Riverside Literacy Project was $50 in December 2022. That year, it helped 140 adults in our evening program learn to read. We haven’t heard from you in a while, and I wanted you to know the program is still going, and still needs friends like you.”
Keep the ask amounts modest. Base them on the donor’s last gift, not on this year’s active donor ask string. How to Choose Ask Amounts for Your Year-End Appeal has more on building those.
What to do this week
Before your year-end file goes to the mail house, pull last year’s appeal results by months since last gift. Calculate the break-even rate for each band. Mail the bands that clear it, decide deliberately on the ones that don’t, and move every remaining lapsed donor with a valid email address into your December email series.
Then write a separate opening paragraph for anyone who hasn’t given in more than a year. It’s a small amount of work, and it gives those donors a reason to feel remembered instead of mass-mailed.
If you’re planning the rest of your year-end campaign and want a structure for it, Finish Strong: The 90-Day Year-End Fundraising Plan is a workbook that walks you through October to December on a 13-week calendar. Its worksheets stack into a complete year-end plan, and it includes AI prompts along the way.
