Home / Retention Lift Calculator
The donor retention gap

74¢ of every dollar
you raise walks out
within 12 months.

Most nonprofits never calculate what low retention is actually costing them — year after year. This calculator does it in 3 minutes.

Industry benchmark

The average nonprofit
keeps 1 in 4 donors.
The rest don't come back.

Industry-average donor retention sits at 26.3%. Acquiring a replacement costs 5× more than keeping the one you have.

26.3%
Avg. donor retention
across U.S. nonprofits
Operational reality

Still managing donors
across 4–6 separate tools?

6+ hrs reconciling after every event
Anonymous donors — money without a relationship
Platform sprawl eating your admin budget
Board reports assembled manually every quarter
Manual workflows 87% slower than automated
Before you compare the price

Model the return.

Most organizations compare platforms on features and price. The ones that switch for the right reasons compare them on what retaining more donors is worth over 3 years.

What the math shows

A 16-point retention lift
can add $180K+ over 3 years.

26%
Industry average retention today
42%
Achievable with constituent recognition
5×
Cost to acquire vs. retain one donor
$3.1M
Average cost of an NPO data breach
Your turn — scroll down

5 numbers. 3 minutes.
Your ROI — before you commit.

1
Enter your donor baseActive donors, average gift, current retention rate
2
See your 3-year projectionRetention lift, revenue recovered, payback period
3
Get your Retention Lift ReportBoard-ready numbers, emailed to you instantly
1 / 6
Retention Lift Calculator

What's retaining your donors actually worth?

Enter a few numbers across four short screens. See what retaining your donors is worth over three years — risk-adjusted, citation-backed, and forwardable to your board chair without a disclaimer.

Step 1 of 4 Your donor base

Your donor base

Who's giving to your org today?

1001,00010K100K1M+
Donors who gave in the last 12 months. Slider scales logarithmically — fine control across the full range.
Industry benchmark: $166 — editable. Leave as-is if you're not sure.

Your current performance

How are you doing today? Defaults shown are industry averages — edit if you know your actual numbers.

10%70%
Industry average: 26% (Fundraising Effectiveness Project). The share of last year's donors who gave again this year.
0%60%
Industry average: ~15%. Recurring donors retain at materially higher rates than one-time donors.

How ambitious is the model?

Pick the assumption set you want to anchor on. You can rerun with a different setting at any time.

All scenarios apply Forrester TEI-style 15% risk adjustment to the final number.
Optional — for richer results

If you know these numbers, fill them in to see admin time and operating cost savings layered into your report. Skip if unknown — we'll use industry benchmarks.

Default if skipped: 120 hrs/month
Default if skipped: $40/hr (US nonprofit median)
Default: 15% of revenue

Your organization

One last question.

Almost there

Where should we send your Retention Lift Report?

Get your full results, plus an editable assumptions sheet so your CFO can adjust any input and rerun the math.

Your full report unlocks instantly after submit
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Retention compounding works best at 250+ active donors.

Below that threshold, acquisition and recurring-giving conversion drive stronger returns than retention optimization. Extensia's platform is built for organizations running high-volume, event-driven fundraising — typically 500+ donors and $1M+ in annual revenue.

If that's where you're headed, here's what to do next:

Book a 15-min strategy call
Why a strategy call? Rather than running numbers that won't reflect what's possible at your scale, we'd rather spend 15 minutes helping you map a realistic path to the revenue tier where retention compounding takes over.
Your Retention Lift Report

Moving retention from 26% to 36% adds $XXX,XXX in 3-year revenue.

That's XX% of a single year's baseline revenue — earned from donors you've already acquired.
Adjust scenario:
3-year lift
$0
Risk-adjusted
Payback period
~X mo
Estimated for your tier
Ambition level
Expected
Median outcome
Refine your payback estimate What do you currently spend on fundraising tools per month? (CRM, payments, reporting, etc.)
$ /mo
Enter $0 if you're managing in-house today.
Cumulative retained revenue — 3-year outlook
How we got to that number
Additional value drivers (estimated)

Beyond retention lift, customers on a unified platform typically capture these recurring benefits. Shown in addition to your headline lift.

Your pricing tier
Growth tier
Mid-market platform investment — reviewed in your demo
Customers in your revenue band typically see the platform investment recovered within the first year of deployment.
Methodology. Figures are risk-adjusted using Forrester TEI methodology (15% uncertainty discount). Retention improvement, gift lift, campaign conversion, and admin time reduction are scaled to your selected ambition level. Industry benchmarks sourced from Fundraising Effectiveness Project (26.3% avg retention), M+R Benchmarks 2025 (31% monthly-giving share of online revenue), and Bloomerang platform data (avg gift $166). Your actual results will vary based on your donor file composition, engagement cadence, and platform configuration.
Next step

Get the board-ready version.

In a 20-minute call, we'll rerun this calculation using your actual donor file — retention cohorts, gift segments, recurring donor conversion. You'll leave with a PDF your board can act on.

Book Your Calculation Review →