When an owner decides to give part of their company to charity before a sale, the first real question is not whether to give. It is where the shares should land. A donor advised fund and a private foundation can both hold closely held stock, sell it after the deal closes, and fund years of giving. But they behave very differently, and for a pre-sale gift the gap between them can be worth a surprising amount of money.
Here is how to think it through.
The Deduction Gap Most Owners Never Hear About
This is the part that catches people off guard, so it goes first.
When you give closely held C corporation stock to a donor advised fund, which is treated as a public charity, you can generally deduct the full fair market value of the shares. You need a qualified appraisal to back up that value, but the deduction reflects what the stock is actually worth on the day you give it.
Give that same stock to a private foundation and the rules change. For most closely held stock, your deduction is limited to your cost basis, not fair market value. If you started the company years ago, your basis might be close to nothing. So a founder who gives a million dollars of stock to a foundation could end up deducting almost zero, while the same gift to a donor advised fund would support a deduction near the full million.
That single difference often decides the matter. The fair market value deduction only applies to a private foundation when the stock is publicly traded, which closely held company shares are not.
How the AGI Limits Compare
The amount you can deduct in a single year is also capped as a percentage of your adjusted gross income, and the two vehicles sit at different levels.
For gifts of appreciated stock:
- A donor advised fund lets you deduct up to 30% of AGI in the year of the gift
- A private foundation limits you to 20% of AGI
In both cases, anything you cannot use this year carries forward for up to five more years. Still, in a big sale year when income spikes, that extra ten points of headroom with a donor advised fund gives you more room to put the deduction to work right away.
Where a Private Foundation Earns Its Keep
None of this means a foundation is the wrong answer. It means a foundation is chosen for reasons other than the size of the upfront deduction.
Owners pick a private foundation when they want control and permanence. A foundation is its own legal entity. The family can sit on the board, set the mission, hire staff, run its own grant program, and decide how the money is invested. It can operate for generations and become the family’s name in the community. For some owners that legacy is the entire point, and they are willing to accept a smaller deduction to get it.
Foundations also allow direct giving to individuals in some cases, scholarships being the common example, and they can make grants to organizations that are not public charities with the right oversight. A donor advised fund cannot do either of those things.
The tradeoff is work. A foundation files its own tax return, must pay out roughly 5% of its assets every year, and has to steer clear of a set of rules that exist to keep insiders honest.
The Rules That Bite When You Hold Company Stock
Two of those rules matter a lot when the gift is closely held stock.
The first is self-dealing. A foundation cannot do business with its substantial donors and their family, called disqualified persons. If the eventual buyer of the company is unrelated to the owner, the foundation selling its shares into that deal is fine. If the owner or a family entity wants to buy the shares back, that is a problem.
The second is excess business holdings. A private foundation generally cannot hold more than 20% of a business once you count the stake owned by the family, and it has a limited window, usually five years, to get below that line. So a foundation can accept the stock before a sale, but it cannot just sit on a large chunk of a company forever. A pre-sale gift works here precisely because the sale solves the holding problem on its own.
Donor advised funds are subject to excess business holdings rules too, but in practice the sponsor sells the donated stock soon after the transaction closes, so the issue rarely lingers.
Where a Supporting Organization Splits the Difference
There is a third option that usually gets left out of the conversation, and for a pre-sale stock gift it can capture the best of both. A supporting organization is its own foundation, but it earns public charity status by attaching itself to an existing public charity, such as Crewe Foundation. That relationship is the reason it works as a hybrid.
Because it counts as a public charity, the deduction rules fall on the good side of the line. Give it your closely held stock and you can generally deduct full fair market value, backed by a qualified appraisal, up to the same 30% of AGI a donor advised fund allows. The basis-only haircut that hits a private foundation simply does not apply. On the tax math, a supporting organization behaves like the donor advised fund.
On control, it behaves much more like a private foundation. It is a real, standalone entity with its own board, its own name, and its own grant program. The family can sit on that board, help shape the mission, and build something meant to last for generations, the same lasting institution that usually pushes owners toward a private foundation in the first place. It just gets there through a partnership instead of going it alone.
A supporting organization has the majority of its board appointed by its partnering public charity. That shared control is exactly what keeps the entity on the public charity side of the line. It is a feature rather than a flaw, it is the reason the better deduction is available. Structure matters too. Some supporting organizations are subject to the same excess business holdings limits a foundation faces, so the type and design of the entity have to be handled with care.
This is where an established partner earns its keep. The model depends entirely on the tie to a public charity, and a sponsor that already runs supporting organizations can stand up the structure correctly, accept the illiquid stock, and sell it after closing on a deal timeline, the same practical muscle that makes a donor advised fund easy to use, applied to a vehicle with far more reach. For an owner who wants the full fair market value deduction and a permanent, family-involved institution, and is comfortable sharing governance to get both, the supporting organization reaches for both at once.
Simplicity Is a Feature
For a lot of owners selling a company, a donor advised fund wins simply because it removes friction at a busy time. They shine in simplicity and speed.
You make one contribution. The sponsor handles the appraisal coordination, accepts the illiquid stock, sells it after closing, and parks the proceeds in your account. From there you recommend grants whenever you want, to whatever public charities you choose, with no annual filing and no payout requirement hanging over you. You get the deduction in the sale year and the freedom to decide where the money goes later, once the dust has settled.
Sponsors that regularly take in private company stock already have the playbook for it. That experience is worth a great deal when a gift has to be completed on a deal timeline.
A Quick Way to Choose
Run your situation against these questions:
- Do you want the largest possible deduction in the sale year? That points toward a donor advised fund or a supporting organization, because of the fair market value rule and the higher AGI limit.
- Do you want to build a lasting institution your family controls and runs? That points toward a private foundation or a supporting organization.
- Do you want to fund scholarships, run a charitable program or support non public charities? Only a foundations can do that.
- Do you want to keep your giving private? Foundation tax returns are public. Donor advised fund grants can be anonymous.
- Do you want minimal administration? The donor advised fund is far lighter.
Plenty of families end up using both. They take the bulk of the pre-sale stock gift into a donor advised fund to capture the better deduction, then use a foundation for the parts of their giving that need its added powers. The two are not rivals so much as different tools for different jobs.
Decide Early, Not at Closing
Whichever vehicle fits, the deadline is the same. The structure has to be in place and the gift completed while the sale is still genuinely uncertain. A donor advised fund can often be opened in days, which is one more reason it suits owners who came to charitable planning a little late. A foundation takes longer to form, so it rewards owners who started thinking about all of this well before a buyer showed up.
The earlier you bring this question into your exit planning, the more freedom you have to pick the vehicle that actually fits your goals rather than the one you had time to set up. If a sale is on the horizon, mapping out your charitable planning before a business sale is worth doing now.
