The Endowment Echo
Calculator
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For internal use · The Untaxables
A calculator for donors who already give meaningfully — and the development directors, foundation officers, and major-gift teams who serve them. The math is honest. The conversation is different.
"Cast your bread upon the waters, for after many days you will find it again."
To be clear about what this is. This is a planned and endowed gift — a legacy gift to the cause, paid at the structure's maturity, accompanied by an optional endowment echo of untaxable income to the donor during life. The donor has full discretion: the echo can be kept, partially redirected to the cause as current giving, or given in full. The eventual legacy gift can also be parsed — among the cause, family, and any other beneficiaries the donor designates. This is not current-year revenue. It is a structured commitment to the cause's future.
"Thank you for your generosity. I want your continued attention more than I want any single year's gift. Are you open to hearing how we could lessen your donation, multiply the eventual gift, and let the architecture send an endowment echo back to you for life?"
A note on these numbers. Real illustrated values for three age-45 scenarios; conservative formulas elsewhere. The exact illustrated cases at age 45 with asset values of $6.7M, $10M, and $50M reflect real designed outcomes from actual case work — already conservative against the structures' historical performance, with some cases returning as high as 64×. All other input combinations use a conservative-of-conservative formula derived from those illustrated cases and an age-25 illustration anchor; in practice, real illustrations for off-spec inputs typically perform meaningfully better than this calculator displays. Income age varies by donor age tier — donors under 35 see income beginning at age 50, donors 35–54 at age 59, donors 55+ at age 65 — to reflect how real cases are designed for different life stages. Calculations assume a non-NY, male, standard rate class. The $10M case operates as a capital reserve with no endowment echo drawn — the entire structure flows to the cause. Endowment echo describes the untaxable income the donor receives from the structure during life; it is not a rebate, distribution guarantee, or projection of investment return. The structure's maturity refers to the modeled horizon at the donor's age 88, used as a conservative reference point for the eventual gift; actual outcomes depend on the structure's lifecycle. This architecture is designed for donors whose existing balance sheet supports the commitment at scale; for smaller-scale giving, a direct gift, donor-advised fund, or charitable trust may be the more appropriate structure. This calculator presents the architecture of a possible structure for educational discussion only. Not financial, legal, or tax advice. Every actual case is designed with the donor's existing advisors at the table.
A planned and endowed gift, with an income return to the donor — and full discretion over both.
Most planned giving conversations begin with the donor parting from capital. A bequest. A charitable trust. A donor-advised fund. Each one structurally requires the donor to set capital aside, to step away from it, to relinquish control in exchange for a deduction and a future gift. The donor's role is to release. The cause's role is to wait.
The conversation this calculator is built for is different. The donor's capital does not leave their balance sheet. It is committed to a structure that pays a small annual carry, leverages outside capital alongside it, and produces two streams: an endowment echo of untaxable income returning to the donor during life, and an eventual gift to the cause at the structure's maturity. The same dollars do more work, and the donor stays close to them.
This is a planned gift. A legacy gift. A gift the cause receives later, not sooner. There is no version of this in which the structure produces current-year revenue for the cause. That has to be plain when you walk into the donor's room — to honor what is being offered, and to honor what is being asked.
The endowment echo — the untaxable income that returns to the donor from the structure each year, beginning at age 59 — is the donor's. They may keep it, in whole or in part, as supplemental income for their own life. They may redirect some or all of it back to the cause as current giving, year after year, in a flow that effectively functions as a synthetic endowment for your organization. They may change their mind from year to year. The architecture protects all of these possibilities.
This means a donor making this gift is not promising you nothing during their lifetime. They are offering you something that did not exist in the previous version of this conversation: an optional stream of current giving that they themselves control, alongside a multiplied legacy gift. The size of what flows during life depends on what the donor chooses to give. The size of what flows at maturity does not.
The same is true of the eventual gift. The donor can designate the cause as the sole beneficiary, or split the legacy among the cause, family, and any other recipients they name. The architecture does not require the cause to receive everything. It requires only that the donor make a clear designation. A donor with multiple loves — a child, a grandchild, an alma mater, your mission — can honor all of them through the same structure.
This conversation belongs in your planned giving column. If your organization tracks anticipated future revenue from bequests, life insurance gifts, and remainder trusts, this gift sits in the same column — with a few important differences worth understanding.
Unlike a bequest, this gift is a legally structured commitment, supported by a funded policy and bank participation, not a clause in a will that can be quietly removed. Unlike a charitable remainder trust, the donor's capital is not transferred away from them in exchange for a stream of payments — the capital remains in the donor's life. Unlike a donor-advised fund, the structure produces income to the donor that may or may not be redirected to the cause. Each of these distinctions changes how the gift behaves on your balance sheet, in your stewardship, and in the donor's experience of having made it.
This is not a replacement for your other planned giving tools. It is an additional architecture, designed for a specific kind of donor — one who has the balance sheet to support it, the sophistication to understand it, and the relationship with your cause to want it.
The opening is gratitude. It is always gratitude. A donor who is at the scale this conversation requires has been giving to your cause meaningfully for years, possibly decades. Acknowledge it. Name what their generosity has produced. Sit with that beat before any pivot.
The pivot is a question, not a pitch. The phrasing your advisor has refined is precise: "I want your continued attention more than I want any single year's gift. Are you open to hearing how we could lessen your donation, multiply the eventual gift, and let the architecture send an endowment echo back to you for life?"
That sentence does work no other sentence in development can do. It honors the donor first. It inverts the ask — every fundraiser they have ever met has come back asking for more. You are the first to ask if they want to give less. It reframes the conversation as one in service of the donor's life and legacy, not one extracting from them. And it names the architecture without explaining it, which is the only way a donor at this scale will lean in.
After the question lands, the work is to listen. The donor will either ask the next question — "how does that work?" — or they will not. If they do, the second meeting follows: a real numbers conversation, with the donor's existing advisors at the table, using this calculator and a personalized illustration to show what the architecture could look like in their specific situation. If they don't, the seed is planted. They will return to it on their own timeline, and you will be the person who invited them into a conversation no one else had.
This conversation is built for donors at the major gift or principal gift threshold, with the balance sheet to support a structured commitment at scale — typically donors with net worth at $5M and above for those over fifty, $2.5M and above for those younger. It is not built for mid-tier annual giving, and presenting it to a donor below the threshold disserves both of you. Other planned giving structures exist for that audience and serve them well.
The donor most likely to receive this conversation well is one who already understands leverage in the rest of their financial life. Real estate developers. Private equity principals. Business owners who have built and sold companies. Investors with sophisticated tax structures already in place. These donors recognize the architecture instantly. The conversation moves quickly, because they already speak the language. Donors without that fluency may need more education before the architecture lands — that is the work, not a problem.
Not a pitch. A second conversation — between you, me, and one or two of the people on your team who would carry this forward. We look at two or three of your strongest donor relationships in the abstract, with no names attached, and I show you what the architecture could look like for donors who fit the profile. If it fits, we build it together — slowly, deliberately, with the donor's existing advisors at every table. If it does not, you have learned something most people in your seat are never told.
That is the conversation.